SPECIMEN PREPARATIONExperiments commenced at the Collector’sEdge laboratories in Golden, Col-orado, in May 1999 to determine the bestmethods for specimen preparation. Aftermany tests, it became clear that heavycoatings could not be removed withoutdamaging the luster of the crystals. Furthermore ,specimens with any degree ofnatural etching could not be improved.Orpiment from Cut 62; 9.5 cm wide. Collector’s Edge specimen. J. Scovil pho..
A second orpiment zone was encounteredin Cut 20 of the North Mega pitduring the fall of 2000, and a Collector’sedge team made over a dozen visits tothe mine, successfully collecting furtherhigh quality specimens during that time. A year later, in the fall of 2001, a final or-piment zone was intersected, again inCut 20, comprising a rich block roughly 3by 4 by 4 m that, fortunately, had beenwell protected from blasting. All togetherso..
Graham Sutton of Collector’s Edge extracting orpiment pocket in Cut 62. Collector’s Edge photo. By April 1999, news of the discoveryhad spread and there was growing ex-citement in the mineral community, andfinding a way of preserving as much ofthe specimen quality material as possiblebecame the first priority. Collector’sEdge presented a proposal to Newmont,suggesting how the two companies mightwork together in a manner tha..
Orpiment collecting operation using heavy equipment. Collector’s Edge photo. The Twin Creeks mine lies at the intersectionof the renowned Getchelltrend and the lesser-known Valmy trend,along which lie a number of other Carlin-type gold deposits. At Twin Creeks theorpiment bodies occur in rocks of theComus Formation, a thick sequence ofcarbonates, siltstones, basaltic rocksand tuffs of Ordovician age which containmost of the sulfide gold ..
Orpiment is not a particularly raremineral. It occurs in many places in lowtemperature hydrothermal veins and inhot spring deposits but is rarely of specimenquality. However,when it occurs aswell-formed lustrous crystals it is highlyprized by collectors on account of itsstriking, honey-yellow to orange-browncoloration. Unfortunately, such specimensaredifficult to extract withoutdamage because orpiment is soft, andthe crystals have perfect cle..