FMF - Friends of Minerals Forum, discussion and message board

[John Betts]

I have three thumbnail specimens from a collection assembled in the mid-1990s. Attached is a photo of a detail and two specimens.

The specimens are spherical formations 10-15 mm diameter and have lustrous black cubic crystals that look like bixbyite intermixed with transparent colorless parallel prismatic crystals that appear to be twinned like reticulated cerussite.

And one specimen has a group of pink cubo-octahedral crystals that could be fluorite. On the pink mineral are platy black-metallic crystals that look like platy hematite.

[John Betts]

The collection had many specimens from Colorado and Utah, but that should not limit your suggestions.

Any suggestions for where these originated and the minerals?

[Bob Carnein]

Can you give us any information about hardness/specific gravity? How about some higher resolution photos? The photos don't blow up very well.

[John Betts]

S.G. will not help as it is a mixture.

No fluorescence.
Not magnetic.
The pink mineral does not react to HCL.

[John Betts]

Here is a larger photo of one.

[Pete Richards]

By golly, I have some too!

I received these as topaz epitactic/pseudomorphic after garnet from the Maynard Claim in the Thomas Range, Juab County, Utah. One of my specimens came from Lanny Ream, and the catalog entry says it was collected in 1994. The other two samples came from Dave Richerson with the same locality data.

While it is hard to see without "wiggling" the specimen around under the microscope, most of the topaz appears to be oriented in several directions consistent with overgrowing garnet.

Bixbyite and possibly hematite are also present; the "hematite" appears to be oriented as well.

Specimens are 1 to 2 cm in diameter.

I have no information about the pink material. Red beryl?

[John Betts]

That's it Pete! Thanks.

[John Betts]

Your pic 2.jpg shows the exact thing I see in person, but was unable to photograph.