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I have collected and dealt in fine Nevada minerals for several years now and have seen quite a few new, exciting finds. Few were as surprising to me as the discovery of a single zone of stunning, brass-colored Millerite found in a localized deposit in the "Barite Vein", 41-20 Heading of the Griffin Ore Body, in the world-famous Meikle Mine (Carlin Trend, Elko County, Nevada). I first saw examples of these specimens at Denver, 2002 and just about fell over from shock! These are not your normal "hair" millerites that sway and break when you breath on them. These are actually sturdy *crystals*, some even being micro terminated! Under a microscope, I have seen hollow, tube-like crystals, branching dendritic groups, sprays and even twisted crystals! These lustrous crystals are typically found growing on pyrite matrix with 3-weight-percent Arsenic. More unusual specimens can have black, silicified jasperoid as matrix. There are also associations of what is likely to be Violarite, FeNi2S4, (unconfirmed as yet) occurring as smooth, metallic gray coating on some of the pyrite matrix. I do not know of any other locality in which millerites of this quality has ever been found on such a matrix. These are also the best-known millerites west of the Rockies and a feather in Meikle's cap! The small, 1-meter-wide zone that produced these specimens has been exhausted now for years. According to the geologists working at the mine, it is unlikely that another such zone will be found. Here's why: If you consider that Meikle is producing 11,000-tons of ore and waste rock per day, every day, and that this mine has been in producing since the mid 1990's, if you do the math you will see that this single zone was a one-in-a-million find. Millerite has been found as micro hairs from other Carlin Trend open pit mines, but these are orders of magnitude better! These specimens are quite shipable, without risk of damage under normal mailing conditions. Enjoy!
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5.5 x 3.2 x 3.0cm miniature specimen of pyrite and black japseroid-breccia
matrix. The specimen shows great contrast between the
darker-gray violarite coatings and the brassy, lustrous millerite
needles to 2mm. |
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5.5 x 3.0 x 3.0cm specimen of pyrite and black japseroid-breccia
matrix, with an open, 1.0 x 0.8cm vug filled with millerite
needles to 0.4cm. |
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4.0 x 4.0 x 2.5cm miniature specimen of vuggy pyrite and metallic-gray
violarite coatings. The millerite occurs as very bright,
brassy sprays with individual needles to 5mm, in several 1 to
2cm matrix vugs- NICE! |
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very nice pyrite/jasperoid breccia matrix measuring 6.5 x 6.4
x 4.7cm, with metallic gray violarite coatings in the vugs.
The millerite occurs as brassy, lustrous needles to 5mm.
One particular millerite vug at the top-center of the
piece measures 1.3 x 1.0 x 0.6cm and is filled with beautiful
millerites! Smaller vugs are present elsewhere on the
front face of the matrix- |
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4.4 x 4.2 x 3.0cm miniature with a fantastic series of
matrix vugs measuring 4.4 x 1.5cm with brassy, lustrous millerite
crystals to 5mm. |
A beautifully-fluted (stalactitic) pyrite matrix measuring 4.8 x 4.2 x 3.0cm, with some violarite coatings. Myriads of millerite sprays dominate the front of the piece, in a 3.5 x 3.0cm area. Single, brassy, lustrous millerites reach 3mm. The fluted matrix displays best on the backside of the piece- |
