The big event of the day was traveling south to the
wholesale shows in south Tucson. Most venues
seem clustered around the Holiday Inn and the Kino Shows and are in the extra-large
“tents.” Inside each tent the numbers of booths and tables are almost overwhelming. Vendors are selling a wide variety of jewelry,
beads, rings, cabs—you name it. We
toured through several of the tents and the displays seemed identical. I could almost believe that the different
rings etc. were all manufactured in the same factory. I also could not observe prices that appeared
to be “wholesale” in nature. Most of the
gems, cabs, silver pieces had lower prices at other venues scattered around
town--or so it seemed. So, off we went
to one of my favorite shows, the 22nd St. venue.
Lots of beads. |
Silver of all sorts, shapes and prices. A great variety of chains. |
From semi-precious to the big boys: rubies, diamonds, sapphires, tanzanite, etc. |
Rings for everyone. Amethyst and red garnets seemed a good buy. |
I wandered through the displays back to the table
featuring Pakistani minerals where previously I had purchased ruby and
spinel. I had remembered the dealer also
had a green mineral for sale that was nicely perched on a white marble—similar to
the ruby and spinel. However, I would
need my best negotiating skills since this green mineral was originally priced
at over my $5 minimum!
I was able to purchase the mineral, pargasite, a sodium,
calcium, magnesium, aluminum silicate that is a member of the amphibole/hornblende
group. The chemical formula is one that
would confuse a beginning mineralogy student: [NaCa2(Mg4Al)Al2Si6O22(OH)2]. As I understand the situation, pargasite is
not only a mineral but part of a “group” bearing its name. Chromio-pargasite
has chromium substituting for the aluminum; in ferro-pargasite iron replaces
the magnesium, fluoro-pargasite has fluorine replacing the part of hydroxyl radical,
potassic-pargasite has potassium replacing the sodium.
Like most hornblende group minerals pargasite occurs
as opaque, dark green to green brown, prismatic to columnar crystals with a
hardness of 5-6 (Mohs). It has a
vitreous to subvitreous luster and the prismatic forms have that diamond shape
cross section created by cleavage angles of ~56o and ~124o.
However, there is a variety of pargasite that is an
electric green color and gemmy and transparent and that is what I purchased. This type of crystal stands out very nicely
on white marble. The specimen came from
the Hunza Valley of Pakistan and was found in metamorphosed carbonate shelf
limestones.
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