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[kent]

A recent backpacking trip found us at a hillside covered with this material. I manage to haul out about 20 lbs., in addition to my backpacking gear...uggg. Just started to cut into it. Looks promising for pendants. Any thoughts on what it is ?

 

[Ranger_Dave]

My guess is chalcedony. Nice stuff. 

[peruano]

I'm guessing not quartz, or if so its a form of onyx.  I'd lean to guessing that its softer than quartz and likely to be a travertine. The breaks on the surface just don't fit with my expectations of a quartz relative.  Either way its pretty. 

[metalsmith]

The patterning looks to be typical of Amazonite - it is not all green - might that be found there?

Again, run some tests in that direction.

[Enchantra]

Looks like perhaps massive aragonite or massive calcite.

Drop some vinegar or dilute acid on an area and see if it fizzes.  If it does, it's probably one of the above.  If it doesn't fizz, then maybe a brecciated agate of some kind that cemented back together with iron containing minerals.

[rocks2dust]

Again, run some tests in that direction.

Good advice. I was thinking something like cancrinite, since with all that granite in the photos, I'd be looking for something igneous or igneous that has metamorphosed. You need to at least establish its approximate hardness. With that, you can compare to lists of minerals with similar hardnesses and look through your state/province's geology department publications to see if anything similar found in that area matches. If you can also get its specific gravity (s.g.) then you'll be well on your way to an identity.

I've seen similar translucent zoning in several materials (e.g., beryl), so appearance is probably the last thing to go on. I agree that it has possibilities for some wonderful cab designs.

[Back]

Hi Kent

The second pic got my eye. I am thinking that pic is dry in full sun light. If so it seems to have a sheen or glow about it like some rough that I have but not cut yet. The question I have does it to the touch feel"different" like smother or more slick then  "normal" stones? If so then I think we both have stuff and I dont have a clue as to what it is.

Bless
Shawn

[kent]

So I went the hardness route. First tried my fingernail then a penny, then a steel knife blade, a steel file and then finished off with the pointed end piece of quartz crystal.  Nothing has scratched this material yet. Tried vinegar with no result. I don't have an accurate scale so determining it specific gravity is out for now.

Shawn, yes the second photo is taken dry. This material has a reflective quality like glass that tumbled down a hill (I know, it probably did)... Interestingly, once we hiked to the top of the ridge we found the largest deposit of white quartz I've ever seen. I literally covered the entire hill. The attached photo is me sitting in the throne....

   

[gemfeller]

Crystalline quartz, i.e. a quartz crystal, is softer than most agates and jaspers.  Try the scratch test using one of the latter.  In fact there's quite a variation in hardness between many agates/jaspers but all types fall in the range of 7-7.5 Mohs.

That last image is pretty impressive.  Is that the source of he material posted, or is it another type of outcrop?  It looks pretty white on my monitor. 

[kent]

I just tried scratching with a piece of sharp stone canyon jasper....nothing.

I'm in the middle of drilling a 1.5mm hole in a small piece to be used as a pendant. Its giving me trouble.....I may try again later when I develop more patience.

Gemfeller...the last photo is on the opposite side of the hill and appears as a different material...looks like your basic white quartz. We found one piece with a vein in it resembling fools gold....Pretty jaw dropping hill....white quartz everywhere....

[Phishisgroovin]

I'm guessing not quartz, or if so its a form of onyx.  I'd lean to guessing that its softer than quartz and likely to be a travertine. The breaks on the surface just don't fit with my expectations of a quartz relative.  Either way its pretty. 

Im leaning towards Onyx also on this one.
Beautiful stuff!
Make some cabs!!!

[Phishisgroovin]

where there is fools gold there is real gold.

[gemfeller]

Kent, if you'll mail me a very small piece of scrap - an inch square or less - I'll check both refractive index and specific gravity.  That'll go a long way toward identifying it.  There are other tests I can do as well.  I'm intrigued by the fact hard jasper like Stone Canyon won't scratch it.   

[Ranger_Dave]

Chalcedony is a cryptocrystalline quartz.  For me, the white quartz on a neighboring hill points to chalcedony. Does it have a conchoidal fracture?

[kent]

Gemfeller...I sent you a PM...