December 2017 Fun Cab Challenge

OK, I found a spare hour today and decided to cut what I thought was webbed variscite. But reading my notes I learned the mineralogist who mined it did some tests and decided it was chalcosiderite. It 's considered a rare copper phosphate mineral with a hardness of 4.5. It 's in what's called a "solid solution" with turquoise which makes sense because this stuff was mined just a few hundred yards from the famous No. 8 turquoise mine in Nevada. No. 8 turquoise often has the same webbed pattern with a black background.

Due to a glitch in my photo program I managed to delete the preform images but it shouldn't make any difference because the stone is a freeform and I make freeforms by removing any parts that don't look like a cab. The finished stone is merely a preform with a polish.

Rough chalcosiderite slab:



Finished cab

Thanks fernwood . I see no amethyst/white on my color-adjusted monitor. Both the rough and finished stone are green and black. I think the colors are more saturate in the polished stone so that may be what you're seeing. It's like colors that are more vivid when rough is put in water to simulate a polish.

Thanks rockjunquie. I've always thought this material is at least the equal of fine turquoise. Too bad it isn't better known. The miner had several hundred pounds of it and entrusted it to a friend who lived near the mine for safekeeping. Before he could return to retrieve it the entire lot was stolen by burglars while the friend was away. So there's more of it out there...somewhere.

^^ who'da thunk that beautiful heart was inside that POS slab! Nicely done.

It actually turned out a bit better than expected, i was expecting less dark blue in it.

Just goes to show never judge a slab until you try, but i have an eye for finding things in the field that will or may be good, im hoping to cut more material like this but i have 1 more slab like it that i know of.


I usually make at least 1 cab from a new found material type just to see how it is as thats the only true way to tell if its good.... if the rock is of interest to me that is. 

I just cut one agate material a couple days ago that is very blue pail to dark in color... i want to find more.. Along with our obsidian which looks nothing like any others ive seen (i think its actually started divitrifying and getting silicated, ive seen some of our obsidian with small agates inside but the rocks weighed 2000 lbs)  Ill be doing a test run of that material some time also.


i just cant wait until my natural citrine i found this year in the fieled is calcite free, im hoping to find crystals in it.  And as everyone knows non heat treated natural citrine is rare to find

WOW, there is a lot of interesting material on show here, and really nicely made too.
I'm afraid, I will be not adding anything new to the lineup. Just an Indonesian amber/copal

The rough
pprough by Kainzer Kurt, on Flickr

Cut into half and trimmed to fit the flashlight
Amber two by Kainzer Kurt, on Flickr

Love the inclusions, but at times they do break the surface
ppUntitled - 2 by Kainzer Kurt, on Flickr

Thanks for looking, Kurt

Great cabs everybody! I planned to enter but ran out of time and energy, with the holidays and such.

I feel your pain.  I got in early, for that very reason.  Here has been below zero highs some days and -25+ wind chill.  Gotta love Winter in Wisconsin.

glennz01 I have my huge fireplace and plenty of wood to supplement my propane heat. Plus, for winter, my living space is cut to about 350 square feet for myself and 3 cats. Mostly living room, with a couch for my bed. Rest is tiny kitchen, dining room, bathroom, utility room and front entry hall. The hall and utility room are insulated, but I need to heat them in winter.