It was interesting to peruse the different booths selling jewelry. Much of it seemed almost identical--pendants of amethyst, agate, sodalite, green stuff marked as chrysoprase, red stuff, blue stuff, dyed stuff, and glass. However, the price varied tremendously between sellers. At any rate it seemed a tough way to make a buck.
Since the theme of the 2019 Show
is WULFENITE IS LOVED, I have tried to
stick in information about each of the samples that I purchased at that
particular venue. One of the small tent
dealers at Kino had some very nice small cabinet to thumbnail specimens
including Arizona wulfenite. So, it was easy to plop down two bucks for some
wulfenite crystals on barite collected from the Puzzler Mine down in Yuma
County. It was interesting to note that
the specimen originally was collected by Shannon Minerals (David?) in the
1990s.
The Puzzler is a relatively
unknown mine for the production of wulfenite specimens; however, it is well
known for its vanadinite specimens. The Puzzler is located in the Castle Dome
District along the Gila River in southwestern Arizona and is but one of many
small mines along the mountain front. It
is somewhat difficult to locate much information on the Puzzler. As best that I can determine the most
important minerals in the Castle Dome mines are “ the argentiferous
galena-fluorite-barite fissure veins in Mesozoic metasedimentary rocks, closely associated
with dike swarms [diorite porphyry].” Much of the shallow ore shows mases of galena
oxidized to cerussite and anglesite.
Vugs within the mrtasedimentary rocks house specimen vanadinite, wulfenite,
mimetite and smithsonite.
Small cluster of wulfenite; matrix is mostly massive barite. Length of cluster ~7 mm.
Wulfenite crystals across matrix. Width FOV ~11 mm.
Wulfenite crystals scattered across natrix. Note the well defined crystal near upper left corner. Unknown dark-colored mineral. The "white-to-clear" mineral may be cerussite or anglesite derived from oxidation of galena. Width FOV ~ 11 mm.
Dense cluster of wulfenite crystals, many very thin tabs. Barite matrix is covered in this area with tiny calcite crystals a a small "blob" of purple ?fluorite. Width FOV ~ 4 mm.
Although mining was occurring in
the Castle Dome District long before Arizona Statehood, it was never an imports
“rich” area, and it seemed a tough place to make a hard living. For example, early miners thought that silvery
galena was almost pure silver. However,
essays indicated on 30 ounces to the ton.
If that was not bad enough, the ore was carried over to the Colorado
Rive north of Yuma, transferred to river boats and carried downstream to the
Gulf of California, transferred to Clipper Ships sailing to a smelter in San
Francisco. Good ore (60% lead and $40 of
silver) brought $90 ton at the smelter with transportation costs of $45
ton. So, there was a profit, enough to
keep small-time miners looking around for richer ore. In the first half of the
20th Century the Castle Dome mines also produced minor amounts of
gold, fluorite, manganese and copper; however, good production records are
unavailable, especially for smaller mines like the Puzzler (MinDat states from
early 1900s to ~1952: 240 tons of ore-- 49% lead, 18 ounces silver per ton. Above information on the Castle Dome District
is from Keith, 1978.
REFERENCES CITED
Keith, S.B. 1978, Index of Mining
Properties in Yuma County, Arizona: Arizona Bureau of Geology and Mineral
Technology, Geological Survey Branch, Bulletin 192.
Wulfenite in the sky.
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