Weloganite Value, Price, and Jewelry Information

Weloganite: Francon Quarry, Quebec Canada (0.37). Photo © Joel E. Arem, PhD, FGA. Used with permission.


An overview on Weloganite Jewelry and Gemstones. Covers details and essential information on the physical properties and characteristics of Weloganite gems.

Weloganite Information

Data Value
Name Weloganite
Colors White, lemon yellow, amber. Crystals may be zoned.
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.
Refractive Index 1.558-1.648
Luster Vitreous.
Hardness 3.5
Fracture Conchoidal
Specific Gravity 3.20
Birefringence 0.090
Cleavage Perfect
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).
Luminescence None reported.
Luminescence Present No
Transparency Translucent.
Absorption Spectrum Not diagnostic.





a = 1.558; β = 1.646; γ = 1.648. Uniaxial (-).

Optic Sign Uniaxial -

Optics: a= 1.558; β= 1.646; γ=1.648.

Uniaxial (-)

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.