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MINERALS ISSUE 1 2010 NEWSPAPER FOR COLLECTORS # . o t . o o t h o p l h i p v l o i c Great new find: v o S c . J S . J In this issue: Adelaide Mine 2010 Tomasz PRASZKIER & Adam WRIGHT Collector interview: Jeff Scovil INTRODUCTION The Dundas Ag-Zn-Pb mining field In this first issue of our news- is located about 10 km east of Zeehan, paper, we start a regular column – The Adelaide Mine, located in and contains a number of mines. Two of interviews with well known and Western Tasmania, is undoubtedly the them are especially productive in terms interesting collectors. For our first in - world’s most famous producer of cro - of crocoite specimens – Adelaide and terview – famous photographer and coite specimens. Only a few great pock - Red Lead. The Adelaide mine however, not very well known collector – Jeff ets with top quality specimens have been produces much bigger quantities of high Scovil !! found in the history of the mine – in quality specimens, including occasional 1970’s, 1990’s and then again in 2010! finds of great pockets filled with the Tomasz Praszkier (Minerals): Jeff The “2010 Pocket” produced a number of world’s best crocoite specimens. – You are probably known to min- world-class specimens with great color eral collectors all over the world ... and exceptional crystal size. Crocoites HISTORY OF THE ADELAIDE MINE from this find are surely among the world’s best. Following is the first writ - The deposit mined recently at the Read on page 13 ten account of this recent find. Adelaide mine was discovered in 1887. The most important period of a large- DUNDAS AREA – WORLD PRIME PRO - scale mining for lead and silver took 1st International Mindat.org DUCER OF CROCOITE SPECIMENS place there from 1890-1915. Crocoites Conference in Poland There are two crocoite producing Continued on page 8 11-17 VII 2011 regions in the Western Tasmania, the Heazlewood district, and the Dundas dis - Crocoite from “2010 Pocket”, The First Mindat.org Interna- trict. 10.1 cm high. Gobin specimen. tional Conference will be held in con - junction with the 14th Lwówek Âlàski Crystal Days Festival, three days of mineral shows, events and live music, where the whole town comes out to celebrate the mineralogical heritage of the region. Visitors can enjoy both Crystalline gold the Conference and the Crystal Days festival at the same time. Read on page 7 from Round Mtn, USA R. Scott WERSCHKY INTRODUCTION Is it a collectors dream, or nightmare? It is easy to justify having one good spec - Imagine going to the Tucson Gem imen from the mine, but does one really and Mineral show, and seeing some new need ten pieces just because they are golds from a mine you have never heard all different? This dilemma has many of. They are leafy specimens with bright, mineral collectors, and especially gold shiny, yellow gold and hints of octahedral collectors, scratching their heads and crystals on the edges. The specimens are then digging deep into the pocket books pretty and inexpensive, and you have to all because the Round Mountain mine have one. Then you return to Tucson the went from being an obscure gold locality . o t next year and see more golds from the to being a world class specimen pro - o h p same mine with even better crystals. ducer virtually overnight. l i v Now do this for several years in a row, o c S . finding different crystal habits, bigger HISTORY . o t J and better crystals, better luster, and o h p larger specimens both on and off matrix! Nevada is known as the Silver State, l i v stemming from the famous silver mines Editors: o c S Crystalized gold from Round Mountain of the Comstock Lode discovered in 1859. Tomasz Praszkier (Poland) . J Prospectors bound for the California Scott Werschky (USA) mine. Size 6.8 cm. Spirifer collection. Associated photographer: Jeff Scovil (USA) Contact: www.SpiriferMinerals.com [email protected] 2 CRYSTALLINE GOLD FROM... MINERALS ISSUE 1 # typified by very fine grained dissemi- USA nation and/or supergene enrichments within silicified tuffs. There are probably RRoundound MMountainountain only a few of these specimens in exis - CANADA qquarryuarry tence, likely well hidden by dust on some geologist’s desk. Ottawa Until the early 1990’s, Round Moun - San Francisco tain was considered to be a very low Round Mountain Washington grade deposit that was remarkable only Los Angeles USA in the total lack of visibly interesting M E rock textures or veining. Things forever X IC changed in March of 1992, when coarse Sign at the entrance to the Round Moun - O tain mine. S. Werschky photo. Mexico gold was found in a blast hole. A routine 5 km ore control assay of blast hole cuttings came in at greater than 30 g/t, quite a Toquima Range in central Nevada, Map of North America with location of Round Mountain and aerial view of the open pit divergence from the expected 0.6 g/t. approximately 240 km east-southeast of mine. Assuming there to be some sort of ana - Carson City. It is in the heart of the Basin lytical error, geologists sampled drill cut - and Range Physiographic Province. Mother Lode found placer gold near shut down completely with the onset of tings piled up around the drill hole. For those familiar with the vast deserts what is now Dayton, Nevada. Although WWII. Round Mountain remained more Processing the cuttings with a gold and mountains of the Western United looking for gold, they struck it rich with or less dormant until the late 1960’s pan yielded more than one kilogram of States, it might appear to be in “the mid - silver at Virginia City just a few kilome - when the Ordich Group picked up the coarse grained gold from what turned dle of nowhere ”. For those lovers of crys - ters north of Dayton. This success with claims. The present day Round Mountain out to be the discovery of the first mod - talline gold, it is arguably “the center silver dictated the exploration focus in mine was commissioned in 1977 with ini - ern day high-grade vein. Since this of the Universe” (at least temporarily). tial inferred (not proven) gold reserves discovery, approximately 150 high grade The original town site of Round Moun - of 18.6 metric tones, and a planned mine life of about 6 years. Through a series of mergers and buyouts, the mine is now a 50:50 joint venture between Barrick Gold and Kinross with Kinross acting as operator. The mine has been in continual operation since 1977, with peak gold production of over 22.7 metric tonnes (730,000 ounces) per year. Total produc - tion to date is nearly 373.2 tonnes (12 million ounces) plus the approximately 10.9 tonnes (350,000 ounces) mined before 1977. Current gold reserves are reported at 46.6 metric tonnes at a grade of 0.64 g/t, with an expected mine life of about 3 years. These figures are based on current gold prices, and future changes may extend the mine life espe - cially if they elect to pursue underground mining. At a minimum, total gold pro - duction for the district will be a stagger - Western portion of the Round Mountain pit with heap leach pads in middle distance, ing 435.4 tonnes (14 million ounces) by and Toiyabe Range in far distance. S. Werschky photo. the time it is mined out! Not bad for a mine that started out with hopes of pro - ducing less than 20 tonnes of gold! veins have been encountered. Projection tain still exists, and is adjacent to the Crystalized gold. Size 8 cm. A. Day coll. The first gold specimens found of the high grade vein trend up to the present day open pit mine. Perhaps 40 J. Scovil photo. during modern mining operations were pre-mining surface on Stebbins Hill cor - people still live there, although the min - relates with veins worked during early ing company is trying to convince them Nevada for the next 40 years. The sub - mining around 1910. Historical research to relocate in order to expand the open sequent decline of the mines of the Com - showed that coarse gold was indeed pit mine to the northeast which would stock lead to renewed exploration efforts known back then as evidenced by photos consume the town. Most of the miners which resulted in several major gold of large gold specimens displayed during live in the small town of Carvers or the rushes in Nevada starting around 1900. a gold mining conference in Chicago, Illi - company sponsored housing in what is Many famous gold mines were found at nois circa 1909. known as the Hadley Subdivision. this time, including Round Mountain It is estimated that more than 9330 which was discovered by Louis Gordon kg (300,000 ounces) of coarse gold have in 1906. In a very short time, there were been recovered since 1992. Unfortu - thousands of miners living in tents and nately, no records exist for historic pro - primitive wooden shacks. At the peak, duction of specimen-grade gold. Round Mountain was producing a lot of 36 kg pile of gold from the high grade After the discovery of the high grade vein! Photo taken ca. 1992 by B. Veek. gold each year, especially considering vein in 1992, geologists at the mine con - the labor intensive mining methods of vinced management to initiate a sales the era. The district produced more than encountered around 1980 in the densely program in which all employees could 300 kg (10,000 troy ounces) of gold a welded tuffs at the top of the caldera buy a few pieces of gold at the prevailing year during early years.
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