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Sunstone in Mexico!
One of the more exciting developments in the mining game this year is the discovery of a
new Sunstone deposit in Mexico.
Located by Ruben Valenzuela in the State of Sinaloa, this new copper-bearing Sunstone from
the Aztecsun mine shows both similarities and differences to the material from Oregon.
In the numerous specimens that I’ve tested, the Refractive Index seems to average
about 0.01 less than the Oregon material.
The crystal structure is certainly triclinic, as shown in the beautiful large specimen-on-matrix below.
The external surfaces of most roughs display the typical
features of gem Feldspar, including the telltale signs
of transformational twinning.
Some of the crystals found here are quite large,
as shown by this specimen on matrix.
The new discovery is very unique because it contains copper schiller, much like that
found in Oregon stones, and so far in a pattern that we would describe as
“snow-flake schiller”, for the relatively even distribution within the stones.
This photo shows copper schiller in a faceted stone.
This oval faceted stone weighing 10.45 carats
shows copper schiller that is very similar in
appearance and beauty to the Sunstone from Oregon.
This rough, weighing 80.5 carats, shows a nice
copper schiller, and will be great for carving.
Another very exciting feature of the Mexican find
is the average size of the stones. This rough
weighs 275 carats - and we have reports of stones
as big as 550 carats.
Larger-size stones are being produced in quantity at the
Aztecsun, as shown in this photograph of recent production.
Something else that I’ve never seen in gem feldspar is the
beautiful smoky-quartz color, shown here in a 50.6-carat
specimen. This coloration is appearing in a significant
percentage of the material from production.
Adding to the unique characteristics of the material
from Aztecsun mine are hollow tube-like voids within
many of the crystals. We’ve seen these kinds of
intrusions in the Oregon material, but usually more
seldom, and usually isolated or in small numbers.
However, some pieces from the new find are completely
shot-through with these fascinating features that
vary in size from almost hair-like to over a millimeter
in diameter.
This 26.6-carat native-cut specimen displays the smoky
color quite nicely – along with some of the black
inclusions that appear to be more common in the new
find than in the Oregon material.
One of the most exciting features of the Aztecsun
material is the size and availability of coveted
“silver schiller” effect stones. We find some material
exhibiting this appearance in Oregon, but they are
usually smaller, less intense, and quite rare.
This 13.5-carat native-cut gem was fashioned from a
rough that looked similar to the one immediately above.
The shimmering effect is very silver with a blue tint.
A few pieces of this material have been found with
such intense shimmering features that they seem to
glow with thier own light.
This is the cabochon cut from that rough, but it seems
impossible to get a photo that does it justice.
The thing just glows from all around.
There are two additional minerals being recovered
from the Aztecsun, including this as-yet unidentified
intense green gemstone.
The other as-yet unknown mineral is a grey metallic
substance that forms in pretty octahedrals, most of
which display some melting. The surfaces of many
of these pieces display an iridescent sheen.
Keep an eye out here – or sign-up for my free newsletter –
for continuing updates from the Aztecsun regarding
production, new material – and availability of
both rough and cut gemstones from this exciting
new find. At this time, we expect production from
this mine to be available through two authorized
dealers at Tucson…
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