Analcime Value, Price, and Jewelry Information

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

Analcime

Large colorless crystals of Analcime are a great rarity although small transparent crystals are abundant. Faceted gems are extremely rare and seldom seen even in large collections. The hardness is marginal for wear, but the mineral has no cleavage and should present no difficulties in cutting.

Analcime Information

Data Value
Name Analcime
Colors Colorless, white, gray, yellowish, pink, greenish.
Hardness 5-5.5
Fracture Subconchoidal
Cleavage Indistinct
Stone Sizes Gems are nearly always colorless and less than 1-2 carats when faceted. Large crystals from Mt. Ste. Hilaire are white but may have small facetable areas. Crystals in basaltic cavities in general do not exceed ¼ inch in size and are transparent.
Formula NaAlSi2O6 · H2O
Crystallography Isometric; good crystals are common, usually trapezohedra. Massive, granular.
Refractive Index 1.479-1.493
Birefringence None. Anomalous in polarized light.
Luminescence Cream white in LW (Golden, Colorado).
Absorption Spectrum Not diagnostic.
Pleochroism None
Optics Isotropic; N = 1.479-1.493. May show anomalous birefringence.
Luminescence Present Yes
Luminescence Type Fluorescent, UV-Long
Luster Vitreous.
Specific Gravity 2.22 - 2.29
Transparency Transparent to opaque.
Phenomena Chatoyancy.

Optics: Isotropic; N = 1.479-1.493.

Occurrence: Secondary mineral in basic igneous rocks; also in sedimentary rocks such as siltstones and sandstones. Washington, Oregon, and California (Columbia Plateau area).

Houghton County, Michigan.

New Jersey: Watchung basalt flows.

India: Deccan Plateau.

Nova Scotia: Bay of Fundy area.

Mt. Ste. Hilaire, Quebec, Canada.

Also Scotland, Ireland, Iceland, Norway, Italy, Czechoslovakia, Germany, Australia.

Comments: Large colorless crystals of Analcime are a great rarity although small transparent crystals are abundant. Faceted gems are extremely rare and seldom seen even in large collections. The hardness is marginal for wear, but the mineral has no cleavage and should present no difficulties in cutting.

Name: From the Greek analkis, meaning weak, because of the weak electric charge analcime develops when it is rubbed.