FMF - Friends of Minerals Forum, discussion and message board

[Bob Morgan]

How about Spodumene. I have a couple of pieces that have etching striations that run that way. There doesn't appear to be any from that area in the photos on Mindat. but maybe...

[Brent Lockhart]

Could it be Barylite? Barylite is monoclinic and is rare, but documented from the Crystal Peak area. Just a wild guess.

[Brent Lockhart]

Opps, make Barylite orthorhombic, my bad. Too many beers last night :)

[Peter Lemkin]

IF that is a phenakite, that is a 'whopper'!! I have collected extensively in the area mentioned, but don't remember seeing anything like that. Also never found phenakite that wan't tiny, tiny, tiny. I sense whatever it is, it may be very large and unusual find for that area, based on my digging there. Don't destroy it. Find someone with Ramen spectragraph or other non-destructive testing method.

[Bob Carnein]

I thought of barylite too, but specimens shown on Mindat have a pretty consistent "look" to them, and none look like this crystal.

[Bob Carnein]

I tried scratching a very flat rhombohedron face on a "Herkimer diamond", and the unknown mineral left some powder and a VERY faint scratch.

[Peter Lemkin]

Since you live not far from where you collected, as you probably know, there are a number of regional experts between where you live and Colo. Springs. If I were you, I'd show it to one or a few of them. One shop in Manatou Springs has some experts in the area, but there are others - some without shops. Just an idea. Perhaps some here can help, but most of us are not local. I used to be living in CO and collected at Devil's Head and that general area often. Never saw anything like you have, but in that P.P. Pegmatite every now and then one would find a very nicely formed XX of a mineral rarely found.....

[Bob Carnein]

I was able to break this crystal into two fragments, preserving the termination. I sent the bottom half to John Attard, who completed an XRD analysis (attached), which indicates that it's quartz. Now the problem is how to explain the crystal habit and forms present. This was a completely unexpected result.

[Bob Morgan]

Quartz does take this habit sometimes. I've heard the nickname of 'saber quartz' for that. Two opposing prism faces are very narrow or completely missing causing it to have a pseudo orthorhombic appearance, hence looking like danburite. It's an oddity and thus highly desirable to certain quartz fanatics. Good find.