Lawsonite Value, Price, and Jewelry Information


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

Lawsonite is extremely rare as a faceted stone, seldom reported and generally unavailable.

Lawsonite Value

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Lawsonite Information

DataValue
NameLawsonite
Crystallography Orthorhombic. Crystals prismatic; massive, granular.
Colors Colorless, white, gray, blue, pinkish.
Luster Vitreous to greasy.
Hardness 6+.
Specific Gravity 3.05-3.12.
Birefringence 0.019.
Cleavage Perfect in 2 directions.
Dispersion High.
Stone SizesThe maximum likely is 2-3 carats. Gems are pale blue in color.
Luminescence None.
Spectral Not diagnostic.
FormulaCaAl­2Si2O7(OH)2 H2O.
Pleochroism Blue/yellow-green/colorless or pale brownish yellow/deep blue-green/yellowish.

Optics:  a = 1.665; β= 1.674-1.675; γ= 1.684-1.686.

Biaxial (+), 2V= 84°.

Occurrence: Low-temperature metamorphic rocks; metamorphic schists; glaucophane schists. Santa Clara, Cuba; Italy; Japan: New Caledonia: France; Italy; other locations.

Tiburon Peninsula, California: original material.

Covelo, Mendocino County, California: 2-inch crystals.

Comments: Lawsonite is extremely rare as a faceted stone, seldom reported and generally unavailable.

Name: After Professor A. C. Lawson of the University of California.