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Hi everyone, I am hoping someone out there might be able to help me identify this rock. It is a beautiful green color, almost like a jade. I have been looking at rocks in the desert for many years, but have never come across this particular mineral before. I don't believe it is related to copper. Any ideas?




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Hello Chris, 
A friend of mine found a similar chunk in the Quartzsite area.  

Another friend found and slabbed the pictured piece in the Gold Basin area.  I too would like to know what kind of rock it is.



Edited by dick ward
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Hi Chris,  

My First Guess... it looks like low quality (1) Nephrite Jade or (2) Chalcedony . very similar... in many ways...  is there Asbestos deposits in the area?     I also notice what looked like some hydrothermal stratification (layering) in the left edge of your photo... maybe (3)  Agate Moss Agate?    All in all... my first guess is probably closest ...

The tables below gives you something to work with... to test your sample...


All the best.


(1) Nephrite Jade: ========================================


Chemical Formula Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2
Jadeite: NaAlSi2O6
Color White, Blue, Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Black, Banded, Multicolored
Hardness 6 - 7
Crystal System Monoclinic
Refractive Index 1.60 - 1.67
SG 2.9 - 3.7
Transparency Translucent to opaque
Double Refraction -0.027 (Nephrite); 0.013 (Jadeite)
Luster Waxy,  vitreous
Cleavage 1 or 2,2 - prismatic. Due to lack of visible crystals, cleavage is rarely observed.
Mineral Class Jadeite or Nephrite (Nephrite can be either Actinolite or Tremolite)


Fresh cut Nephrite Jade slab:  in British Columbia Canada


(2) Chalcedony: ========================================


this piece is from South Africa.

Chemical Formula SiO2
Colour White, Blue, Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Black, Banded, Multicoloured
Hardness 6.5 - 7
Crystal System Hexagonal
Refractive Index 1.54 - 1.55
SG 2.63 - 2.65
Transparency Translucent to opaque
Double Refraction .009
Luster Vitreous to waxy
Cleavage None
Mineral Class Quartz (Chalcedony)



(3) Moss Agate : =========================================



Chemical Formula SiO2
Composition Silicon dioxide
Color Multicolored in banded formation. Colors include white, blue, red, green, yellow, orange, brown, pink, purple, gray, and black. Some rarer forms of Agate are iridescent.
Streak White
Hardness 7
Crystal System Hexagonal
Crystal Forms 
and Aggregates
Agate is a banded microcrystalline form of the mineral Quartz, and does not occur in visible crystals. It occurs in nodules, in massive form, as botryoidal, mammilary, and stalactitic formations, as smooth rounded pebbles, as amygdules, and as the linings of geodes.
Transparency Translucent to opaque
Specific Gravity 2.6 - 2.7
Luster Vitreous
Cleavage None
Fracture Conchoidal
Tenacity Brittle
Other ID Marks 1) Commonly fluorescent, usually green or white. May even show fluorescent banding patterns where some of the bands will fluoresce more strongly than others.
2)  Triboluminescent
3)  Piezoelectric
Complex Tests Dissolves in hydrofluoric acid.
In Group Silicates; Tectosilicates; Silica Group
Striking Features Banding patterns
Environment Agate occurs in all mineral environments, but it is most prevalent in igneous rocks such as basalt.
Rock Type Igneous, Sedimentary, Metamorphic
Popularity (1-4)  1
Prevalence (1-3)  1
Demand (1-3) 1





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Wow, thank you guys for all the great input!!!

Dick, I have found a similar looking rock up at Gold Basin, but instead of green it was purple. I once heard flourite as a possibility?

Gerard, I really appreciate all the photos. I have not heard of asbesotos in the area, but that doesn't mean its not there. I will do some research on nearby historical claims and see what they list as commodities. Chalcedony appears to be a good possibility. Thank you again!

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