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Category Archives: Minerva Reefs

Queensland gold – gold maps

Posted: June 21, 2016 at 6:45 am

Pikedale (32km north-west of Stanthorpe). Records show that the auriferous reefs were small but fairly rich. They were worked by small parties, and were generally abandoned about the 30m level. No general statements can be made regarding future prospects of these mines as the factors leading to their closure are unknown. Near Warroo 32km further west, a gold-bearing lode was exploited to a reported depth of 60m until local smelting became unpayable. Texas (85km by road west of Stanthorpe). The old Silver Spur Mine, 11km east of Texas, produced considerable amounts of silver, lead, gold and copper, the zinc contents remaining in the slag dumps. Existing workings, to 152.5m depth, offer possibilities for further prospecting, but unwatering and reconditioning would be necessary. In recent years interest has been displayed periodically by various mining organizations. Warwick Fields. Warwick (256km by rail or 161km by road south-west from Brisbane) is the base for the following gold fields Talgai (34km west-south-west), Leyburn (45km north-west), Canal Creek (45km south-west), Lucky Valley (19km south-east), Palgrave (34km south-west) and Thanes Creek (39km west). With the exception of Canal Creek, which was purely an alluvial field, the history and present condition of these old fields are very similar. They have been practically worked out as far as alluvial gold is concerned. In the primary deposits, payable gold values occur in narrow shoots in small fissure veins which could not at the time of working be profitably followed much below 30m Where there is reason to believe that the shoots were not worked out further prospecting in depth might be justified. Moreton District. The low-grade gold deposit at Kingston (24km south of Brisbane) was worked for a number of years by a syndicate, but is now deserted. Gold occurrences near Ormeau (48km south of Brisbane), and Camp Mountain (16km west) do not offer much inducement for further prospecting. North Arm (117km by rail north of Brisbane). The discovery of auriferous quartz reefs in a hitherto unproductive series of volcanic rocks was made in 1929. Company operations were carried on till 1938 within a relatively small area, but all efforts to locate workable auriferous deposits further afield resulted in failure. It is of interest to record that the free gold is so highly alloyed with silver that it is almost white in colour and is associated with the rare mineral naumannite (selenide of silver). Gympie (170km by rail north of Brisbane) The highly auriferous reefing area at Gympie was confined to a heavily faulted strip about 3km long by 1km wide This small area has been responsible for a large proportion of the fields production. Operations were ultimately continued to depths of considerably over 600m on the Monkland end of the field. The mines of the main belt form an extensive connected group, now filled with water. Owing to the prohibitive expense involved in dewatering and reconditioning these mines, it is doubtful whether any of the connected group of workings can be deemed worthy of further consideration. Since the decline of major mining operations -about 1917, numerous attempts have been made to exploit blocks of shallow ground. Relatively few of these attempts have met with success. Far-many years production was maintained by cyanidation of old tailings, but this has now ceased. Mary Valley (south from Gympie). Alluvial and surface gold deposits were originally worked on a small scale near 1mbil (40km by rail from Gympie) and a small production has been won intermittently from quartz veins occupying minor fissures in granite. Glastonbury (13km west of Gympie). Gold-bearing quartz reefs occupying fissures occur in altered sedimentary rocks near a granite contact. They vary in thickness from a few cm to about 1m. The output from the field has not been large. Small-scale operations were formerly conducted by a company which operated a small battery and concentrating plant. Yabba Goldfield (32km north of Kilcoy); also known as the Jimna field. It was essentially an alluvial field, and is credited with rich returns in the early years from deposits on Jimna and Sandy Creeks. Reef-mining followed on a small scale for some years with two plants on the field. A few small reefs carrying fair values have been worked in recent years. Kilkivan (72km by rail and 48km by road west of Gympie). On this old goldfield, restricted but rich shallow alluvial deposits were worked and reefing followed. There has been little gold production for about sixty years, but a few men have been engaged near the town and on the Gold Top provisional field, 8km distant. Copper deposits were worked to a small extent at an early period at Mount Coora, Mount Clara and Black Snake. Re-opening of an old cupriferous gold lode at Black Snake in 1939 resulted in productive operations, with crushing, tabling, flotation and cyanidation plant on the ground, till 1949. Recently, several deposits in the area have been the subject of Departmental investigation by drilling. At Tansey Creek near Goomeri, an auriferous formation had been worked to a depth of 87m when work ceased in 1942. Recent dewatering and sampling indicated erratic distribution of values in the bottom workings. Marodian Goldfield (13km north of Kilkivan) Alluvial gold was found on Colo Flats and at Yorkeys Hill. Little work has been done on the field for many years. Nanango (209km by road north-west of Brisbane, and 27km from rail at Kingaroy), Gold deposits near the town, at the Seven-mile diggings (alluvial only) and also at Scrub Paddock (32km north-east) were worked at an early stage in the States history. The last period of marked activity included an attempt by an English company to work a group of auriferous copper veins at Scrub Paddock. Despite intermittent prospecting over the wide area available, no discoveries of note have since been made. Prospecting of small auriferous reefs and leaders has been carried out near Emu and Possum Creeks in the Blackbutt area without marked success. Small deposits of silver-lead and of gold-bismuth have been worked near Mount Langan in the same area. Proston, (116km by rail west of Gympie), Some gold prospecting has been carried out in the Boondooma area, some 32km west of Proston, but nothing of importance has been recorded. Gold and antimony have been prospected at Glenbar (40km south-west of Maryborough). Biggenden (87km by rail west of Maryborough), A deposit of magnetite at Mount Biggenden was worked intermittently for its gold and bismuth content until 1938. Paradise Goldfield (13km north-west of railway at Degilbo), Stanton-Harcourt Goldfield (18km north of Degilbo, and Mount Shamrock Goldfield (19km west-north-west of Degilbo). These three small goldfields were worked towards the end of last century. Apart from a small amount of prospecting, little work has been done for many years. A little gold was also won on the Chowey, Mount Steadman and Gebangle fields a few kilometres further west. In the Mundubbera district gold prospecting was formerly carried on at d**ehead (29km west) at Hawkwood (48km west-south-west) and at the old Brovinia diggings (64km south-west of Mundubbera) but no discoveries of significance have been made. Eidsvold Goldfield (224km by rail from Maryborough). A group of auriferous fissure deposits was extensively worked between 1888 and 1900. An unexpected collapse of the field followed failure of values in the deeper levels of the principal mines. Although the reef formations proved to be persistent in depth subsequent efforts railed to locate workable shoots. Activity since 1906 has been limited to intermittent small-scale operations. On St. Johns Creek, 26km south-west of Eidsvold, large quartz lodes have been worked spasmodically for antimony and gold. Cracow Goldfield (95km by road west of Eidsvold). Discovered in 1931, this field for some years has been the only major producer of gold in Queensland, apart from Mount Morgan. Total output of fine gold to the end of 1974 was nearly 19 000kg most of which came from the Golden Plateau mine. Long narrow ore-shoots in quartz-calcite veins were worked at the Roses Pride and Klond**e mines to depth of 40m and 45m respectively. At Golden Plateau a zone of quartz deposition up to 76m wide and nearly 800m long occurs beneath a sandstone capping. Several irregular tabular ore-shoots have been mined and the lowest productive workings are at the 252m level. Diamond drilling was successful in locating additional ore-shoots within the mine leases. In the Bundaberg district, mining for copper and gold has been carried out extensively at the Tenningering field (108km from Bundaberg, with Mount Perry as its centre), and Boolboonda field (90km from Bundaberg). Gold reefs have also been worked at Reids Creek. There has been very little mining in recent years although prospecting is being continued by several groups. Lode rutile has been found as shoad in the foothills of Mount Perry and traced to limited outcrops. A little gold has been won from a deposit at Swindon (22.5km east of Mount Perry), from which coarse alluvial gold was shed, but there is little prospect of other than small-scale production. THE STANTHORPE DISTRICT (GSQ Report 64) Gold was first discovered at Lord Johns Swamp (Lucky Valley Goldfield) in 1852. In 1863 rich but limited alluvial gold was uncovered on Canal Creek. Following close on the Canal Creek discovery were further finds at Talgai (Darkies Flat 1863-64), Thanes Creek (1869), Pikedale (1877), Leyburn (1872), and Palgrave (1877). Canal Creek was an alluvial goldfield only, where as both alluvial gold and reef gold were won from Talgai. Thanes Creek was primarily an area of reef mining; at Pikedale and Leyburn little or no alluvial gold was won. Little is known of the Palgrave field. The period of principal production was prior to 1905. Attempts at revival of reef mining in the 1930s were only moderately successful, and did not survive for long. Any future prospects appear to lie in further development or known reefs below the old shallow workings.

Alice River (or Philp) Gold and Mineral Field.

Gold was discovered in the upper reaches of the Alice River in 1903 by the prospector thingyie. From 1904 to 1909 mining was virtually confined to the Alice Queen and Peninsula King reefs, and since 1917 the field has received little attention. The total recorded production from 1903 to 1917 is 3.3kg of gold from about 2800 tonnes of ore, together with 14kg of alluvial gold. Between 1904 and 1909 the Alice Queen reef produced about 37kg of gold from 1570 tonnes of ore, and the Peninsula King reef about 31.1kg of gold from 632 tonnes of ore.

The two reefs lie within 1.5km of each other on a north-north-westerly line. The Alice Queen mine in the north is in a vertical quartz reef between 1 and 2m wide and over 100m long (Cameron, 1906). Of the two shafts, the southerly was 34m deep in 1906. The quartz from the mullock dump contains small grains of pyrite and stibnite. Felsite d**es trending south-southeast cut the altered Kintore Adamellite to the west of the workings. The Peninsula King reef is 0.5 to 1m wide. In 1906 several shallow shafts had been sunk along the line of the reef.

In the Potallah Creek Provisional Gold Field

only one reef, the Perseverance, has been recorded. It is situated in fine-grained schist of the Holroyd Metamorphics about 1km west of a stock of Kintore Adamellite. According to Cameron the reef trends north and is 75cm wide at a depth of 12m. The only recorded production is 18.26kg of gold from 593 tonnes of ore in 1903-04. A shaft was sunk at Potallah Creek in 1946; the reef at a depth of 33m is reported to have been 2m wide with a grade of 15.6g of gold per tonne.

Jensen recorded a small number of gold occurrences in the Potallah Creek area. Production of 0.16kg of gold is recorded from Olain Creek in 1914 (probably OLane Creek, 13km north-north-west of the Potallah Creek shaft).

Hamilton Gold and Mineral Field

A sma1l rush followed the discovery of gold by thingyie at Ebagoola early in 1900. Gold was found farther south near the Lukin River in the following year. Peak production was reached in the first year when about 470g of gold, 342kg from alluvials, was recorded. Mining virtually ceased during World War 1 and has been sporadic since. Total production from 1900 to 1951 was 291.58kg, made up of 1371.63kg of reef gold from 34196 tonnes of ore, 682.41kg of alluvial gold, and 237.54kg from the treatment of 19 256 tonnes of tailings.

Mining at Ebagoola was centred about the old townsite. The Yarraden mining area, about 15km south-southeast of Ebagoola, extends for 8km from the Lukin River southwards to Spion Kop; it does not include Yarraden homestead. Gold occurs principally in numerous quartz reefs.

Ball reported that the reefs in the Ebagoola area trend roughly north along the contact between the older granite (Kintore Adamellite), which he considered to be metamorphosed, and the schist and gneiss to the east (Coen Metamorphics). He believed that the reefs were related to the newer granite (Flyspeck Granodiorite); in the Yarraden area the reefs occur within the Flyspeck Granodiorite. In the Ebagoola area quartz occurs as leaders, veins, or compound reefs.

The leaders are up to 15cm wide and occur mainly in shrinkage cracks in the granite. Although they are of limited length or depth, and are seldom rich in gold, most of the alluvial deposits were probably derived from them. True fissure reefs, such as the Caledonia and All Nations reefs, occupy shears along the contact between the metamorphic and granitic rocks. The compound

fissure veins are associated with acid d**es, or with beds of quartzite, such as the May Queen reef.The water-table is generally at a depth of less than 20m in the dry season, and consequentlysulphides such as pyrite, arsenopyrite, galena, and stibnite are found almost at the surface. Mining was generally not profitable at grades below 47g of gold per tonne.

The most productive workings in the Ebagoola area were the Caledonia, Hamilton King, MayQueen, Hit or Miss, Violet, Hidden Treasure, All Nations, and Golden Treasure. In the Yarraden area the two most important reefs were the Golden King and Savannah. According to Cameron, the Golden King reef trends roughly north, dips vertically, and ranges from 15 to 40cm wide; it was worked over a length in excess of 300m to a maximum depth of 65m. Mining was almost continuous between 1901 and 1915, and was resumed in 1917 and 1921.

Recorded production is 239.84kg of gold from 7699 tonnes of ore. The Savannah reef lies about500m east of the Golden King and dips steeply west. It is more than 30m long with a steep southerly plunge. Mining was carried out to a depth of at least 38m. Between 1901 and 1907 and in 1912 a total of 2761 tonnes of ore yielded 156.51kg of gold. Attempts to reopen the mine in 1939-40 were unsuccessful.

*Minor production in 1930s included.

Other reefs of importance in the Yarraden area were; the Lukin King with a total production between 1901 and 1926 of 63.73kg of gold from 1631 tonnes of ore, the Gold Mount which yielded 2.99kg of gold from 781 tonnes of ore between 1901 and 1921, and thc Hiaki (or Haikai) which produced 39.22kg of gold from 1622 tonnes of ore between 1909 and 1918.

Alluvial mining was mainly restricted to the Ebagoola area and most of the production was before 1910. The gold was coarse, and was derived mainly from eluvial deposits shed from nearby reefs and leaders.

The Coen Gold and Mineral Field

was proclaimed over an area of 95km2 in 1892 and enlarged to 480km2 in 1898. Alluvial gold was discovered at Coen in 1876 and in 1878 there was a small rush from the Palmer River, but few miners stayed more than two weeks and the workings were abandoned in the same year. In 1880 Chinese miners attempted to work the alluvium without success.

In 1885 land was taken up for mining silver, and machinery was erected in 1886, but productive

reef mining did not start until 1892. Between 1893 and 1899, 16689 tonnes of ore crushed at Coen yielded 888.1kg of gold. Ball visited the field in 1900 and recorded mining activity at Coen town, at The Springs 15km to the south-east, and at Klond**e 13km north-east of The Springs.

According to Ball the reefs are from several centimetres to 1.5m thick, and generally trend north-west to north, with a steep dip. Most of them are fissure veins composed of quartz, but a few consist of siliceous slate; some of the poorer reefs contain pyrite or arsenopyrite.

The most successful mine was the Great Northern. About 1km south-east of Coen township; it has produced about three-quarters of the gold won from the field. Other productive reefs near Coen, which were mined mainly before 1900, were the Daisy, Hanging Rock, Homeward Bound, Lankelly, Long Tunnel, Trafalgar, and Wilson reefs. Between 1894 and 1899 the Great Northern mine yielded 230.85kg of gold with a high silver content from 4394 tonnes of ore. In 1900 activity at Coen came almost to a standstill when the Hamilton goldfield was opened, but gold continued to be won at Coen for many years, mainly from the Great Northern and from the treatment of tailings with cyanide.

The total recorded production of reef gold at Coen from 1892 to 1916 was about 2333kg, of which 2172.86kg came from the Great Northern mine, including 412.4kg from the treatment of 20 000 tonnes of tailings and mullock. The total amount of ore recorded between 1812 and 1916 was 28 185 tonnes, of which 26 234 tonnes came from the Great Northern mine. After 1910 production fell off rapidly, and in 1914 only 7 tonnes of ore was mined.

The Great Northern mine was reported to have been worked to a depth of 150m, but little work was done at that depth. The north end of the No.4 level, somewhere below 54m, was reported in 1909 to be 78m from the shaft. The reefs in the lower levels ranged in width from 75cm to 1.2m. After 1909 production came from small rich leaders in the hangingwall and footwall above the No.3 level possibly at 54m. Little is known of the mine after 1914, but attempts were made to reopen it as late as 1949.

Mining was carried out at The Springs, 15km south-east of Coen, from the early 1890s to about 1901. The main reefs were the Westralia, where 455 tonnes of ore were crushed for 19.56kg of gold in 1901, the Goolha Goolha, the Rothwell, and the Sirdar, where 207 tonnes of ore produced 13.41kg of gold beween 1898 and 1901. This part of the Coen Field was abandoned during the rush to the Hamilton goldfield in 1900 and 1901.

At the Klond**e, 13km north-east of The Springs, the Springfield reef yielded about 40kg of gold from 366 tonnes of ore between 1898 and 1902. The Klond**e lodes trend roughly north and occur in schist and gneiss of the Coen Metamorphics near their contact with the Lankelly Adamellite.

The workings at Coen and The Springs lie within or adjacent to the Coen Shear Zone. The zone extends for about 27km south-east of Coen and lies largely within the Lankelly Adamellite and along its southwest margin. The schistose sheared adamellite contains a little pyrite and arsenopyrite. Quartz reefs are common along the shear zones, and in the south they are up to 5km long and 100m wide. Most of the mullock dump at the Great Northern mine, which lies in the shear zone, consists of a breccia composed of fragments of silicified granite set in a matrix of white quartz; the country rock is sheared Lankelly Adamellite. The quartz and gold were probably deposited from hydrothermal fluids introduced after the rocks were sheared.

In the Blue Mountains,

40km north of Coen, which are not included in the Coen Gold and Mineral Field, gold was mined from some time before 1934 until 1951. The gold occurs in narrow quartz veins in granite. The total recorded production in 1935, 1938-46, and 1948-51 is 33.53kg of gold from 950 tonnes of ore; of this 17.5kg from 593 tonnes came from mines operated by Blue Mountains Gold N.L., principally the Golden Ladder and the Convict. One of the other major producers was the Yarraman mine. No mines were operating in 1967.

A small number of leases have been held in recent years in the Leo Creek area, 30km north-east of Coen, but no production is recorded. In the Nullumbidgee area a few kilometres to the north 3.5 tonnes of ore yielded 0.40kg of gold.

The small Lochinvar Provisional Goldfield on Tadpole Creek, about 18km southwest of Coen, is situated in Kintore Adamellite. The only recorded production is 2.2kg of gold from 50 tonnes of ore in 1904.

Rocky River Gold and Mineral Field

Alluvial gold was discovered in the Rocky River, 32km north-east of Coen, in 1893 by Lakeland. Reef mining began on Neville Creek (location unknown) in 1896 and the field was proclaimed in 1897. Between 1896 and 1901, 951 tonnes of ore yielded 142.64kg of gold. Interest waned in 1901 following the discovery of the Hamilton goldfield, but it revived for a short time in 1910 and 1911 when 57 tonnes of ore yielded 8 77kg of gold. Jack noted that only four people lived on the field in 1914, and there were no returns that year. No mines were located in 1967.

Hayes Creek Provisional Gold Field.

Jack recorded traces of gold in Hayes Creek, 60km northeast of Coen, during his 1880 expedition, and the area was later visited by thingyie and Campbell during a prospecting journey to Lloyd Bay in 1907. Shepherd records that the Hayes Creek field was discovered in 1909, but this probably refers to the start of reef mining on the Golden Gate claim.

Production has been small and spasmodic. In 1909 production from the Golden Gate claim was 37 tonnes of ore which yielded 6.81 kg of gold and a further 1.71 kg on cyanidation. In 1911 production from the field was 3.18 kg of gold from 21 tonnes of ore. Production in 1914 was

1.14kg of reef gold and 0.37kg of alluvial gold. The field was deserted in 1915. Some prospecting continued until 1938, and between 1938 and 1942 some 150 tonnes of ore were crushed for a yield of about 6kg of gold. In the early 1950s small parcels of ore are reported to have yielded between 80 and 120g of gold to the tonne, and one 4-tonne crushing returned 0.2kg of 850-fine gold.

Shepherd noted four sets of workings at the main centre at Buthen Buthen. At the Theodore lease a quartz reef between 30 and 35cm wide was exposed for 65m, with a strike of 140 and dip of 47 to the south-west; the reef contained a little pyrite and arsenopyrite. The 20cm reef on the Diana Lease contained pyrite and a little free gold; on the Campbell and Buthen Buthen leases Shepherd saw only shallow trenches and small shafts. At Companimano Creek, 6km south-south-west of Buthen Buthen, a quartz reef 90cm to 1.2m wide contained gold, galena, pyrite, and arsenopyrite.

The reefs in the Hayes Creek field are situated in a northerly trending shear zone in Kintore Adamellite; the valleys of the Lockhart and Nesbit Rivers follow this zone. In 1964 the valley of the Nesbit River between Buthen Buthen and Kampanjinbano (Companimano?) Creek was investigated as an alluvial gold prospect, and an almost enclosed basin on Leo Creek, 8km southwest of its junction with the Nesbit River, was also tested, but little gold was found.

Wenlock Gold and Mineral Field.

Gold was discovered in 1892 at Retreat Creek, a tributary of the Batavia (Wenlock) River and later at the site of Bairdville. Further prospecting, mainly between 1905 and 1911, disclosed several small alluvial deposits at Downs Gully, Choc-a-block Creek, and other nearby sites. The amount of gold produced up to 1910 has been estimated at 93 kg. In 1910 an aboriginal prospector named Pluto located a large lead at the base of the Mesozoic sediments overlying the Kintore Adamellite; the locality became known as Plutoville and was rushed by miners from Coen and Ebagoola. According to Fisher the early workings covered an area of about 350m2, and consisted of shallow alluvium and small reefs, which were worked to a maximum depth of 5m. Morton mentioned a shallow lead of cemented wash with rich gutters at the workings. Total recorded production from Plutoville is estimated at 190kg of gold. The Main Leader about 5km north-east of Plutoville was discovered in 1922 It consists of a narrow quartz reef with payable gold for over 300m along strike. The discovery became known as Lower Camp and later as Wenlock. Fisher described the Main Leader as a north-westerly trending fissure reef, with a few cymoid loops, which dips at 60 to the south in the north and 35 in the south. In the south it is cut by the Main Reef, a quartz reef over 6m wide.

The average width of the Main Leader is 20cm, and its walls are slickensided. It contains free gold to a depth of at least 100m, or about 30m below the water-table. Connah stated that the Main Leader is composed of quartz with a distinctive white and blue banding, and ranges in thickness from 2 to 45cm. Short rich shoots with a northerly pitch are common, and coarse particles of gold are evenly distributed in the reef, with a few rich local concentrations. Fisher estimated the average grade at about 50g of gold per tonne. The Main Leader occurs in Kintore Adamellite and is overlain by Mesozoic sediments and alluvium. The deep leads at the base of the Mesozoic sediments on the west side of the Main Leader also contain gold. Connah found that the main deep lead was a narrow rich gutter which spread out into a wide drainage channel trending west-south-west.

He has suggested that the extension of the channel beyond the workings is down thrown by a fault trending south-east. This may be the continuation of a post-Cretaceous south-easterly trending fault, downthrown to the west, which was mapped in 1967, 13km south-east of Wenlock. Total production from Lower Camp is estimated at 1089kg.

The Wenlock field was deserted during World War II. The claims along the Main Leader were amalgamated in 1946, but operations ceased again in 1952, partly as a result of flooding in 1950. Prospectors have continued to be active around the field, and in 1964-65 it is reported that 87.09 kg of gold were obtained from 2 tonnes of picked specimen stone.

Gold was first produced from the Claudie River Gold and Mineral Field

in 1933, the field was proclaimed in 1936. The gold was mined at Iron Range, Scrubby Creek, and Packers Creek. Shepherd (1939) gives the total production from 1935 to June 1938 as 17 331kg of gold from 6104 tonnes of ore and 1067 tonnes of tailings. Iron Range produced 13 421kg from 3753 tonnes of ore, Scrubby Creek 33.65kg from 1984 tonnes of ore and 1067 tonnes of tailings, and Packers Creek 544kg from 376 tonnes.

The largest reef, Gordons Iron Range, yielded 1084kg of gold from 2568 tonnes of ore. The average yield from the rest of the field was 162g per tonne. The field closed in 1942 for the duration of the war. A little mining was carried out after 1945, and between 1950 and 1953 the Cape York Development Co. attempted without success to develop a few of the mines at Iron

Range. Total recorded production from the field between 1934 and 1942 is 333.12kg of gold from 17100 tonnes of ore and 3221 tonnes of tailings. Production since the War has been small, but a little gold is still obtained from a mine at Packers Creek. At Iron Range the gold occurs in quartz veins and lodes in schist of the Sefton Metamorphics,

while at Scrubby Creek and Packers Creek the gold-bearing lodes and veins are in the Weymouth Granite. At Iron Range, the deposits are large but low grade in the iron-bearing schist, but small and rich in the adjacent iron-free schist (eg. the Iron Range reef); the reefs occur along fault lines in the schists.

South-east of Iron Range some of the reefs are parallel to the schistosity and others have components both along and across the schistosity; short ore shoots occur where the reefs intersect.

North of Iron Range the lodes, such as the Peninsula Hope and Northern Queen, are composed of crushed sericite schist with quartz stringers. Broadhurst & Rayner suggested that in the primary zone the ore shoots will prove to be lenses of silicified schist impregnated with sulphides, chiefly arsenopyrite. Rayner noted the discovery of a wide body of sulphide ore on the Peninsula Hope lease at Iron Range, and a CSIRO report on the treatment of arsenical gold ore from the Peninsula Hope mine gave the head assay of the ore as 18.2g of gold, 1.8g of silver, 4.4% arsenic, 20 7% iron, 9.79% sulphur, and less than 0.05% copper. The sulphides are arsenopyrite and pyrite, with some altered pyrrhotite and traces of chalcopyrite, sphalerite, and gold. The gold and sulphide minerals at Iron Range may have been introduced by the Kintore Adamellite, as elsewhere in Cape York Peninsula, or by the Weymouth Granite.

Gold was discovered in the Possession Island Gold and Mineral Field

in Torres Strait in 1896, and production began in 1897; Jackson described the mines he visited in 1901. All the workings are near the north-west coast, east and north-east of the monument to Captain Cook. Mining was carried on until 1906 when the leases were abandoned. Attempts were made to reopen the workings in 1919, and again in 1934-35, but without success. Recorded production between 1897 and 1905 is 155.42kg of gold from 7245 tonnes of ore, including some returns for the Horn Island Gold and Mineral Field. Four tonnes of ore yielded 0.09kg of gold in 1919.

Jackson noted that the main workings were located on two almost vertical reefs about 230m apart, which trend south-south-east. The reefs consist of quartz veins, up to several centimetres thick, in a matrix of fractured and altered welded tuft; the veins contain a small quantity of sulphide minerals. Jackson also noted severa1 shafts and small cuts, and records that a sample of ore, composed of vein quartz with galena and pyrite, assayed 57.95 g of gold and 33.9g of silver to the tonne.

Copper-staining associated with limonite has been noted in the chloritized and silicified welded tuff northeast and southwest of the abandoned workings. Northeast of the workings some galena and pyrite have been observed in joints. Alluvial gold was discovered in the eastern part of Horn Island in 1894 and the Horn Island Gold and Mineral Field was proclaimed the same year. Reef mining began in 1895 or 1896 in an area of about 0.5km2, 1km inland from the east coast. The mines are situated in altered and silicified porphyritic microgranite to the south of a stretch of sandy alluvium. Recorded production is 31.07kg of alluvial gold between 1894 and 1896, and 176.67kg of gold from 16 904 tonnes of ore between 1896 and 1900. The recovery of gold declined sharply in 1900, and by 1901 the field was almost deserted.

Most of the reefs are steeply dipping and trend east-southeast or southeast. They consist of closely spaced quartz veins in altered microgranite. Sulphide minerals were found in many of the reefs only 3m below the surface. Pyrite and galena are the most common sulphides, but some of the reefs also contain sphalerite and two contain chalcopyrite. The average yield decreased from 30g per tonne in 1896 to 20g per tonne in 1900. Sporadic production continued on a small scale until 1919, and prospecting went on at intervals until 1966.

Australian Selection Pty Ltd drilled three holes to depths of about 75m in 1963, but did not consider the prospect payable; an ore concentrate assayed in 1961 yielded 750g of gold and 440g of silver per tonne. In 1965 overburden was removed and 120m3 of alluvium were taken for sampling but the results are not known.

A visit to the mines in 1968 revealed a large open cut, probably on the Welcome reef, about 100m long by 50m across, and a smaller open cut, in the vicinity of the Dead Cat claim, with a timbered shaft in the bottom. In the smaller open cut the porphyritic microgranite is yellowish green and intensely altered; it is cut and silicified by numerous quartz veins. The altered rock contains small patches of sulphide minerals. In the larger pit the microgranite is less altered and contains fewer quartz veins; the sulphide minerals occur in small veins. Pyrite and galena are common, and chalcopyrite and a little wolfram(?) were also observed.

Elsewhere, minor amounts of gold are reported to have been won on Hammond Island between 1907 and 1909, and possibly until 1919, and on Thursday Island in the 1930s.

Extract from Bureau of Mineral Resources Bulletin No. 135:


Mining activity is recorded to the north-west of Cordalba on the southern side of the Burnett River. The area has been a small producer of gold and silver.


No official records are available prior to 1933, but it is reported that the Wild Irishman Mine was worked as early as 1883. Mount Ideal, near Cordalba, was prospected about 1895. Most mining activity took place in the 1930s.


Gold mineralization is recorded from three mines -Wild Irishman, Bull Ant, and Mount Ideal. The Wild Irishman Mine, 13 miles north-west of Cordalba, was first worked about 1883, but was soon abandoned. The lease was taken up again in 1933. The country rock consists of very altered, sheared sediments (Biggenden Beds) with quartz veins, intruded by aplite and granite of probable Permian to Triassic age. The intrusive rocks are sheared. Discontinuous reefs consist of vitreous quartz with minor iron oxide and arsenopyrite. They range in thickness from 18 inches to 2 feet. The reef system is parallel to the Electra Fault and appears to be cut off in depth by a parallel fault. In 1934, 80 tons of ore yielded 51.2oz of gold.

The Bull Ant Mine, 11 miles north-west of Cordalba, was prospected in the late 1890s. The reef consists of quartz and iron oxide; the country rock is sheared sediments (Biggenden Beds) with quartz veins. The mine is on a very wide shear zone. Low gold and silver values are recorded.

Mount Ideal Mine is on the west bank of Woocoo Creek, 2 miles south-west of Cordalba. The reef was probably worked about 1895. The country rock consists of altered sediments (Brooweena Formation) containing masses and veinlets of quartz with pyrite, arsenopyrite, and a little gold. Mineralization is confined to a faulted area of 40 feet by 100 feet. Gold values were found to be associated with siliceous material which formed only a small part of the mineralized zone. No workable ore bodies were located.


Three proclaimed mining fields and one provisional mining field lie within the Sheet area. Gold was also found in a number of other areas and some gold deposits were located outside proclaimed fields. Most of the gold was mined from reefs; however, alluvial gold was won from the Hungry Hill -McKonkey Creek -Coonambula area. Except for the lodes of the Cracow area, virtually all the gold occurrences are associated with the granitic rocks of the Permo-Triassic Rawbelle Batholith.

The auriferous quartz reefs occur in these rocks or in the adjacent country rocks. They are largely confined to the eastern and south-eastern parts of the batholith and the nearby Eidsvold Complex. The reefs occur in the less acidic phases, which may represent the oldest parts of the batholith. They do not appear to occur in any preferred structural orientation. Many of the reefs in hornfelsed country rocks are associated with acid or intermediate dykes and occur relatively near the contact with the batholith. Except for the Cracow lodes, the mineralization has been of minor importance.

Cracow Mining Field

Payable gold was discovered in 1931 by C. Lambert and partners, working under an incentive from the Government. Several mining companies operated the field and gold was won from the Golden Plateau, Golden Mile, Roma North, Roses Pride, Golden West, Dawn, Lamberts Surprise, Revival, and Klondyke. All but one mine had closed by the end of 1951. The Golden Plateau mine, operated continuously by Golden Plateau N.L. since 1933, is the only major producer and for many years Golden Plateau and Mount Morgan have been the only important gold producers in Queensland.

The total production to the end of 1972 was 1 453 144 tonnes of ore milled for a yield of 18314.33kg of gold and 19 036.29kg of silver. Average grade is approximately 12 9 per tonne. Annual production figures are listed in thee table.

The gold deposits occur in andesitic volcanics of the Lower Permian Camboon Andesite. The regional strike is north-north-west and the dip 25 west. The volcanics unconformably overlie acid volcanics of the Carboniferous Torsdale Beds which are intruded further to the east by Upper Carboniferous granitic rocks and the Permo-Triassic Rawbelle Batholith. The unconformity is exposed approximately 4km east of the Golden Plateau mine. Rhyolite dykes are associated with some of the gold mineralization; the remainder is localised by fault zones. The age of the dykes and the faulting is not known; however, a Late Permian to Early Triassic age of mineralization is considered most likely.

Although several small lodes have been worked on the Cracow field, gold deposition was confined mainly to the Golden Plateau lode system which Brooks (1965) considered to form a faulted link between the White Hope lode on the west and the Golden Mile lode on the east.

Within the Golden Plateau lode, irregular tabular ore shoots have been mined discontinuously over a length of 693m, a width of up to 15m. and to a depth of 252.5m. The lode system is terminated abruptly on the west by the north-north-west striking Golconda Fault and on the east by a fault of similar strike. These faults were probably initiated prior to ore deposition, but post-ore movement has also taken place.

The gold occurs as gold-silver alloy in a quartz gangue. Primary gold is seldom visible to the naked eye, even in high grade ore. Small quantities of sphalerite, chalcopyrite, pyrite, galena, bornite, and hessite are present.

The Golden Plateau lode is regarded as a hydrothermal replacement deposit. The mineral assemblage and gold fineness suggest that ore deposition took place near the base of the epithermal zone. Ore deposition seems to have been controlled by faults, and in many places appears to be related to rhyolite dykes. Brooks notes that nearly all ore shoots have one wall defined by a fault plane or fault zone. In the eastern section of the mine, ore shoots often occur adjacent to a rhyolite dyke, or they may be confined between a fault and a rhyolite dyke. The mineralization is Post-Lower Permian (Camboon Andesite) and pre-Jurassic ( Precipice Sandstone).

Between 1960 and 1971 diamond drilling by the Queensland Department of Mines on behalf of Golden Plateau N. L. resulted in the discovery of a major oreshoot in the Golden Plateau area and the proving of depth extensions of the main Roses Pride oreshoot. This major oreshoot has been the principal contributor to the production of gold and silver from the Golden Plateau mine since 1965. In 1969 Golden Plateau N. L. deepened the Roses Pride main shaft and drove a level a distance of 208.5m at a depth of 74m to follow up drilling results. In view of the marginal grade of the ore the company did not proceed with production.

Eidsvold Mining Field

Gold was discovered in the Eidsvold area in 1858, but early activity was spasmodic. The first prospectors claim was taken out in late 1886 over an area of land near the wor kings at Eidsvold head station on the north bank of the Burnett River. Initially . the mining activity was centred on Mount Rose ( later Eidsvold) and Craven Town, 5.6km south-west of Mount Rose on the Burnett River. The Eidsvold Goldfield, which included an area of 28.5km centred on Eidsvold, was proclaimed in 1887.

Gold was mined continuously in the field from 1887 to 1914, with the peak production in the period 1893 to 1900. The maximum gold produced in one year was 426.80kg in 1892. With the discovery of payable gold at Cracow in 1931, interest in the Eidsvold field was renewed, and gold was mined intermittently until 1950. The total recorded production between 1886 and 1950 is 3011.91kg of gold from 90 025 tonnes of ore.

The mineralization occurs in the granitic rocks of the Upper Permian to Lower Triassic Eidsvold Complex and in isolated areas within adjacent Lower Permian(?) hornfelsed sediments and volcanics of the Nogo Beds. The gold occurs in quartz reefs. Hydrothermal solutions from the reefs have resulted in the kaolinization of feldspars up to a few metres from the contacts.

The main reefs, Mount Rose, Stockman or Lady Augusta, Craven, and Maid of Erin, are all located in the Mount Rose area, just west of Eidsvold. Rands noted that the majority of reefs strike north-west to north-north-west and dip easterly at angles from 20 to 45 . The reefs consist of quartz and minor associated pyrite, chalcopyrite, and sphalerite (Maid of Erin reef), stibnite and cassiterite (Stockman reef), galena (All Nations reef), molybdenite ( Moonlight reef), and arsenopyrite.

The Mount Rose reef strikes east-north-east and dips 25 south-easterly. Rands reported the reef to average 75 cm in width, and consist of layered quartz, and interbedded clayey material, with the best gold occurring in the quartz.

The Lady Augusta or Stockman reef strikes north-west and dips 22 north-east, with the principal part of the reef dipping 65. Rands noted that the Empress Shaft on the Lady Augusta reef line was sunk to 247m, cutting through the probable extension of the Mount Rose reef at a depth of 119m. The Lady Augusta reef averaged 9 cm in width, but varied at depth from 15 to 20 cm. Generally, the gold occurs in hanging wall leaders in association with quartz and calcite. Rands also noted the occurrence of massive stibnite in a shaft south-east of the Augusta mine (523m due south of the court house and 91m north-east of the outcrop of the Lady Augusta reef).

Rands reported that the north-west-striking and shallow dipping Craven reef has a thickness of 18 to 20 cm and an average gold content of 122g per tonne. The Maid of Erin reef strikes north-west with a north-easterly dip and is approximately 1.2m wide. It contains little quartz and occurs at the contact between granite and diorite. The Lady Minerva reef. striking north-east and dipping approximately 27 south-east has an average width of 8 cm in the underlie shaft. Rands described the Lady Rose reef, which outcrops 362m north of the outcrop of the Mount Rose reef, as a 30 cm wide quartz vein with copper staining in an altered granitic formation within the granite.

During the early years of development of the Eidsvold field, prospecting parties discovered gold occurrences in several adjacent areas. The Queen Bee and Mount Jones prospecting claims were granted in 1887 for areas on the Burnett River, approximately 14.5km north of Eidsvold head station. Considerable development was undertaken, but the only recorded production was that for 1889 when a crushing of 10.16 tonnes of ore yielded 1.41kg of gold.

The Lady Amy claim, approximately 1.2km west of Eidsvold, was located on the line of a fissure in granite marked by a white kaolinized band striking 80 and dipping 15 south. In contact with this kaolinized band is a brown limonitic band up to 1.8m thick, which contains little quartz, but hosts the gold mineralization. A sample from the south-easterly dipping gold bearing formation yielded 4g of gold per tonne.

St John Creek Mining Field

Gold was discovered at St John Creek in 1888. This discovery, at first in alluvium and later in reefs, produced a drift in population from the dwindling Craven Town areas to the St John Creek area. The 5km2 goldfield situated 26km south-west of Eidsvold, was gazetted in 1890.Few reports on the area exist. The two main mines on the field, Perseverence and Burnett Squatter, were worked intermittently between 1888 and 1937. The total recorded production from the field since 1888 is 313.03kg of gold from 15 669 tonnes of ore milled. Peak production was achieved in 1890 when 98.35kg of gold were obtained from milling 7574 tonnes of ore.

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Republic of Minerva Tonga | Atlas Obscura

Posted: June 12, 2016 at 8:24 pm

Although many utopian societies seem doomed from the outset, the Republic of Minerva was up against a unique challenge: creating a libertarian micro-nation on reclaimed reefs in the Pacific Ocean, when the land already had an owner.

Situated 250 miles from Tonga, the Republic of Minerva was conceived by wealthy Nevada real estate mogul Michael Oliver. According to Oliver, his organization the Ocean Life Research Foundation had raised $100 million to create a utopian society on Pacific reefs. Oliver's plan was to create a micro-nation without taxes, welfare or economic intervention, that lived chiefly off of tourism and fishing.

In 1971, Minerva's construction began by bringing barges of sand to the reefs to raise them out of the ocean. Oliver then led a conference of neighboring states in which he delcared his intentions, only to find out that Tonga had issued a claim over the land. At that point, Oliver and his organization jumped the gun a little bit. Ignoring other claims to Minerva, Oliver issued a declaration of independence and created a coin currency for his new nation and was all set to launch into his experiment in nation building.

Unfortunately, the King of Tonga did not accept the new country's legitimacy, and issued a document laying official claim to the reefs. Within months, representatives from Tonga made it clear they were in control of the reefs, and Oliver and his followers left without a fight.

Since that time, a few other groups have tried to set up shop on the islands of Minerva, only to be rebuffed once again by the Tongan government. Almost all of the land brought to the reefs has since been reclaimed by the Pacific Ocean.

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Minerva Reef Directions | Island Cruising Association

Posted: at 8:24 pm

Minerva sailing directions South Pacific voyagers, particularly those bound from Tonga or Fiji for largely cyclone-free New Zealand, should keep North and South Minerva Reef in mind for a possible storm refuge, rest stop, adventure destination, or at the very least as a potential hazard to navigation. These two atolls also represent an opportunity to see tropical Indo-Pacific sea life in a nearly undisturbed condition. Weather windows The best times to visit the Minervas are either northbound during the late Southern Hemisphere fall near the end of May/ early June or southbound during the late spring in October. Arriving too early (northbound) or too late (southbound) invites exposure to severe weather conditions. Depart New Zealand for the voyage north right behind an outgoing low, not in the middle of a high, and embark from the Minervas southward just as the leading edge of a preferably mild high reaches the area.

Information sources British Admiralty Chart 985, Mi nerva Reefs.: accurately depicts both atolls and includes a close-up of the pass into South Minerva useful for orientation. Approximate CPSentrance coordinates, for use in good light in conjunction with the chart and a lookout only, are 230 37.36 S, 178056.11 W (North Minerva) and 23 56.55 S, 179007.60 W (South Minerva). Sailing Directions Planning Guide for the South Pacific Ocean (Publication 122) also contains useful data for a visit to the Minervas. General layout North Minerva Reef is nearly circular, with an approximate diameter of 3.5 nm. Using a proper lookout, one can move around inside the atoll in order to anchor in the greatest protection for the prevailing wind. South Minerva Reef consists of two roughly circular rings of reef joined in the middle, like a number 8 tilted slightly in a northeast-southwest orientation. Only the two-milediameter eastern lagoon is accessible to larger vessels, and anchoring in Herald Bight, outside the pass, is tenable for wind directions lacking a northerly component. Like North Minerva, movement throughout this eastern lagoon for optimal anchoring is possible with a vigilant lookout. We noted a narrow pass on the northern rim of the western lagoon not shown on the chart, potentially navigable for centerboarders and dinghies. Good holding ground is prevalent inside both Minervas, and both feature slightly

bumpy conditions at higher tides in normal weather conditions. Gear A fully stocked medical kit, manuals, and training; good longdistance communication capability, such as single-sideband or ham radio or an Inmarsat transceiver; and survival fishing and watermaking equipment are all critical for a trip to the Minervas. Fishing and diving gear will greatly enhance your pleasure and dinner menu. Specifically, bring medium to heavy trolling gear for offshore fishing, 10- and 20-poundclass spinning rods for lagoon fishing, wetsuits for diving and snorkeling in the cool water, thick dive boots or other protective footwear for reef walking, and a Hawaiian sling and lobster snare. Jurisdiction The Minerva Reefs were ceded to Tonga in 1972 and ratified by the South Pacific Forum the same year. In 2010 Fiji disputed the Tongan ownership and placed gunboats at North Minerva to try and force their claim. The claim is currently under dispute.

Obviously,you will have either cleared customs out of Tonga or not yet checked in when you visit. The Minervas, however, have been long considered a stopover between countries, certainly in severe weather or for vessel repairs. Nevertheless, go easy on the seafood harvest, never taking more than you can consume in a short time, and do not disturb giant clams, sea turtles, or other threatened creatures. A visit from a Tongan patrol boat should not, under these conditions, be cause for concern.

This entry was posted on Monday, April 25th, 2011 at 2:19 pm and is filed under Cruising Guide, Resources. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

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Minerva Reef Directions | Island Cruising Association

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