Gaylussite Value, Price, and Jewelry Information


Gaylussite
Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons

This mineral is very hard to cut because of extreme softness and cleavage. Gaylussite dries out slowly in air and the surfaces may turn white. Stones in collections are therefore best stored in sealed containers to prevent dehydration. Gaylussite is seen only in very comprehensive collections, and relatively few stones have been cut. Transparent crystals are not terribly rare, but faceted gems are relatively uninteresting.

Gaylussite Value

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Gaylussite Information

DataValue
NameGaylussite
Crystallography Monoclinic. Crystals elongated, flattened, and wedge-shaped.
Colors Colorless, white, grayish, yellowish.
Luster Vitreous
Fracture Conchoidal; brittle.
Hardness 2.5-3
Specific Gravity 1.995
Birefringence 0.077
Cleavage Perfect 1 direction.
Stone SizesCrystals from Searles Lake have been found up to 2 inches long. Gems cut from such crystals could be up to about 20-30 carats.
Luminescence Weak cream white in SW (Nevada). May be triboluminescent.
Spectral Not diagnostic
FormulaNa2Ca(CO3) ·5H2O
Pleochroism None

Optics:  a = 1.445;β= 1.516; γ= 1.522.

Biaxial (-), 2V = 34°

Occurrence: In alkaline lakes or evaporite deposits rich in borax.

California: Searles Lake, Owens Lake, China Lake. Borax Lake.

Wyoming; Nevada.

Mongolia, China.

Venezuela: in clay beds.

Kenya: in transparent crystals, from Lake Amboseli.

Comments: This mineral is very hard to cut because of extreme softness and cleavage. Gaylussite dries out slowly in air and the surfaces may turn white. Stones in collections are therefore best stored in sealed containers to prevent dehydration. Gaylussite is seen only in very comprehensive collections, and relatively few stones have been cut. Transparent crystals are not terribly rare, but faceted gems are relatively uninteresting.

Name: After the eminent French chemist, Professor L. J. Gay-Lussac.