An overview on Weloganite Jewelry and Gemstones. Covers details and essential information on the physical properties and characteristics of Weloganite gems.
The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.
|Crystallography||Hexagonal; crystals hexagonal, barrel shaped with heavy striations on prism faces, also grooved due to oscillatory growth. Crystals distinctive, terminated by pedion or pyramids. Also massive.|
|Colors||White, lemon yellow, amber. Crystals may be zoned.|
|Cleavage||Perfect; fracture conchoidal.|
|Stone Sizes||Clean, yellowish stones (mostly under ½ carat) have been faceted from this material. National Museums of Canada (Ottawa, Ontario): 4.27 (light greyish-yellow); 0.52 (light yellow).|
Optics: a= 1.558; β= 1.646; γ=1.648.
Occurrence: In an alkalic sill intruding a limestone at St. Michel, Montreal Island, Quebec, Canada.
Name: For William E. Logan, first director of the Geological Survey of Canada.