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These
fantastic getchellite, orpiment and stibnite combo specimens come from
the collection of a former Senior Mine Geologist at Getchell. Between
1988 and 1989 in the South Pit of this famous gold mine, collecting was
done in a series of unique, highly-mineralized getchellite zones, right
when it was best exposed in the pit wall during commercial mining. The
pieces were kept in 2 large sample bags and preserved for mineralogical
and petrographic analysis. After these studies, the remaining
material was placed in storage and forgotten. In 2004, they were
rediscovered and seen in a whole new light. Once the chunks of horribly-filthy
orpiment were cleaned and trimmed down, stunning cherry-red getchellite
CRYSTALS could be seen!
This was a very exciting find, since the getchellite occurrence
at the Getchell mine has been completely mined-out for over 15 years now.
To this day there remains no hope for present or future finds of the mineral
from this mine.
Getchellite is almost unheard
of in showing any crystal faces. It is almost exclusively
seen as cherry-red, mica-like cleavages. To see even the tiniest
bit of a crystal face is extraordinary. In general, I would rate
getchellite crystal faces to be more rare than even lorandite crystal
faces. At Getchell, getchellite cleavage planes over 5mm are unusually
large and rare, as well.
Getchellite is a very interesting
and unusual mineral species. First found at the South Pit of the
Getchell mine and named back in 1965, This cherry-red, micacious mineral
best resembles orpiment in crystal habit. In fact, chemically, the
only difference between the two species is that half of the Arsenic in
the orpiment crystal structure has been replaced with Antimony, to make
getchellite. Interestingly, many of the specimens represented in
this lot show a very unusual habit of grading in and out of both getchellite
and orpiment in the same crystal cleavage face.
These bi-colored crystals are attractive and
unique! Notable examples are mentioned in the descriptions.
In
this lot, the main focus on the pieces are of the developement and size
of the getchellite crystals. The richness and coarseness of
the getchellite cleavage planes are also important, as many are exceptional
in size and quality for Getchell. I also like the specimens that
have some micro stibnite associations. This species locks in the
mineralogic circle of chemistry- Orpiment, Arsenic-Sulfide;
Stibnite, Antimony-Sulfide; Getchellite, Arsenic-Antimony-Sulfide. These
are by far the finest and largest getchellite crystals and cleavages ever
to come from Getchell. When these examples are gone, there will
be none to replace them with.
These
notable specimens have been prominently mentioned in the Mineralogical
Record (China Issue, What's New at Denver 2004, Page #114)
ENJOY!
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