Thursday, March 28, 2019

PUZZLER MINE WULFENITE: EXPLORING TUCSON SHOWS, KINO PARK


I always wanted to buy a real antique rock!

After wandering through the 22nd Street Show I decided to wander some more and headed to the wildest show in Tucson, the Kino Gem & Mineral Show over at the Kino Sports Complex.  This Show has always had a variety of sellers with goods often not expected at rock and mineral shows.  At one time there were numerous small sellers with tents and pickups with a variety of nice mineral specimens.  A few years ago, most were eliminated due to “space limitations.”  There are still plenty of dealers and many of the outside small tents have some bargains with the minerals. One of the larger tents houses an uncounted number of jewelry dealers while another has a variety of lapidary equipment. 
 
One can observe many items "for sale" at Kino including coon skin hats and animal skins, cattle hides and baby elephants as seen in the above pictures.  I was not allowed to take photos of the firearms.
This was a beautiful table made with polished slabs of labradorite (a plagioclase feldspar exhibiting a play of color).

Many stands had "large rocks" for sale.  I certainly could not have lifted one of these to the car!

This shop was quite bust selling less expensive sterling/gemstone jewelry.
Beads, beads and more beads at almost all of the Tucson venues.  However, I did not see a "big run" on buying as in some previous shows.  Is the bead frenzy slowing?

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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