Lazulite

Lazulite

By Tim Matthews, JD, FGA, GG, DGA,
CEO and President of JTV (retired)
Published: June 2014
Modified: May 2022
Lazulite Polished Lazulite Rough

This mineral species can be opaque to crystalline transparent. The color of lazulite ranges from medium to dark greenish blue to violet blue and is often mottled with white. When fashioned into gems, finished stones typically weigh less than 5 carats. A separate mineral species, lazulite should not be confused with lazurite or azurite.

General Information

Common Name
Lazulite
Species
Lazulite
Transparency
Transparent - Opaque
Dispersion
Strength: None
Refractive Index
1.604-1.663 Tolerance: (+0.005/-0.005)
Birefringence
0.031- 0.037
Optic Character
Biaxial
Optic Sign
Negative
Polariscope Reaction
Aggregate (AGG), Doubly Refractive (DR)
Fluorescence
SWUV: inert
LWUV: inert
Pleochroism
Trichroic, strong dark violetish blue, colorless, and light blue
Hardness
5.5-6
Streak
White
Specific Gravity
3.090-3.240 Typical:3.090
Toughness
Poor
Inclusions
Transparent material is highly included. Aggregate lazulite material will have a mottled appearance with white areas.
Luster
Vitreous
Stability
Brittle
Fracture
Splintery, Uneven
Cleavage
Good, in one direction, Poor, in one direction
Chemical Name
hydrous magnesium iron aluminum phosphate
Chemical Formula
MgAl2(PO4)2(OH)2
Crystal System
Monoclinic
Chemistry Classification
Phosphate

Lazulite Colors

  • Black Lazulite
    Black
  • Blue Lazulite
    Blue
  • Brown Lazulite
    Brown
  • Green Lazulite
    Green
  • Yellow Lazulite
    Yellow

Alternate Names

Bluespar

Countries of Origin

Myanmar; Afghanistan; Russian Federation; Czechia; United States of America; Madagascar; United Kingdom of Great Britain and Northern Ireland; Portugal; Austria; Sweden; Pakistan; Morocco; Unknown; China; Ireland; Brazil; Slovakia; Bulgaria; Chile; France; Argentina; Hungary; Japan; Rwanda; Switzerland; Bolivia (Plurinational State of); India; Spain; Canada; Norway; Namibia; Finland; Italy; Zimbabwe; Antarctica; Australia; Peru; Germany

History

Gets its name from the German word "lazurstein" which means blue stone.

Care

Lazulite is brittle so please handle with care. It is slowly soluble in acid in hot acid.