DENVER SHOW 2015: COBALT MINERALS

Photomicrograph of pink crystals from specimen below.  Width ~7 mm.

Although I sort of hobbled around the displays at the recent Denver Show (see posting September 21, 2015), I was able to visit a few dealers and make several small purchases.  I am always looking for some special minerals, especially those with nice crystal form and color.  Therefore, I was excited to see some specimens collected from Bou Azer, Ouarzazate Province, Morocco.  A recent post (July 13, 2015) described several cobalt minerals that are a bright pink in color.  The minerals I purchased ($5 or less per specimen) include: roselite [Ca₂(Co,Mg)(AsO₄)₂-2H₂O], cobaltoan calcite [(Ca,Co)CO] and erythrite [Co₃(AsO₄)₂-8H₂O].  Although I had these minerals in my collection, the newly purchased ones are larger and “nicer.”  All are idiochromatic minerals whereby cobalt, with its distinctive coloration, is included within the crystal lattices.

Colbaltoan calcite crystals width ~4 cm.  Camera would not pick up the vibrant pink color.

Another specimen of cobaltoan calcite.  FOV ~1.3 cm.

Nice crystals of fibrous erythrite from specimen below.  Width of crystals 1 cm.

Fibrous erythrite scattered across specimen. Width ~7cm.

Streak of roselite crystals.  Width ~4.5 cm.

Photomicrograph roselite crystals from specimen above.  Width ~ 1 cm.

 It ain't over till its over.  So long Yogi, I guess your earthly stay is over.  You were my hero.  RIP 1925-1915.

1953 "baseball card."  public domain.

                                                   

DENVER SHOW 2015

The 48th edition of the Denver Gem and Mineral Show opened on September 18, 2015.  The Show is sponsored by the Greater Denver Area Gem and Mineral Council and is currently housed at the Denver Mart north of downtown and adjacent to I-25 (for easy access).  In addition to the "main event" nine other shows are scattered across the city starting on September 11 or 12 and extending to the 20th.  There are something like 850 different vendors displaying their wares at the ten shows; however, the "main event" is the show with the competitive cases and displays by various museums and clubs.  The street talk is that Denver is the second largest venue after Tucson and one needs all week to visit the several opportunities.

Jack Thompson, a longtime member of the Colorado Springs Mineralogical Society is an expert in judging competitive display cases.

I usually attend the "main event" in order to see the various display cases and ogle at the minerals and wonder why my expeditions have never produced such fine specimens?  This year was a little different as my newly replaced knee and my upcoming new hip really slowed down the walking.  I was essentially confined to the center stage of the Mart and unable to visit the various hallways with fine mineral and fossil dealers.  But, I am hopeful that the new body parts will allow much more mobility in the near future!

My favorite display was Minerals and the Instruments used to Study Them exhibited by Dan and Dianne Kile.


The theme for the 48th Show was Minerals of the Southwest so I expected numerous specimens of Arizona azurite and malachite; the exhibits did not disappoint.  There were several cases displaying minerals from Utah, especially large nodules of variscite and crandallite.  These two aluminum phosphates are greatly sought after by collectors, especially those collected form the Little Green Monster Claim in Clay Canyon near Fairfield in Utah County.  This mine was worked by two collectors with connections to the Colorado Springs Mineral Society---Ed Over and Art Montgomery.  

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The green to yellow phosphate nodules containing variscite [AlPO₄-2H₂O] and crandallite [CaAl₃(PO₄)(PO₃OH)(OH)₆] collected from the Little Monster Claim are probably the “best in the world.”

This specimen came from Arizona and is a great azurite.

I have never collected Arizona Fire Agates but certainly observe such in dealer displays.

Beautiful malachite from the Bisbee Copper Queen Mine.

I thought this specimen from Bisbee was particularly nice.

New Mexico furnished some nice specimens but not many cases dedicated to the state. Certainly the smithsonite shown below was a nice eyeopener. 

These Thunder Eggs collected from Little Florida Mountains near Demming, New Mexico, have spectacular colors and patterns.

Nevada is a top gold producing state and specimens were in abundance. 

I have never seen such a display of quartz scepters. 

 A mighty large hunk of turquoise from Cripple, Creek, Colorado.

 

 

 

I thought these stone intarsia boxes were absolutely amazing.  They were constructed by Nicolai Medvedev and are housed at the Lizzardo Museum of Lapidary Arts.

And no Denver Show would be complete without Mr. Bones and Moroccan fossils.