Cavansite
Cavansite
Published: June 2014
Modified: October 2021
Very distinctive in appearance, cavansite is a rare, not to mention strikingly beautiful, blue mineral. Its name is derived from its composition: calcium, vanadium and silicon. Only discovered in the 1960's in Oregon, cavansite is highly sought after by mineral collectors across the globe. Found in a scant few locales, cavansite sources include Brazil, India, New Zealand and Oregon USA. It is renowned for its stunning deep blue hues that are sometimes vivid enough to be described as "electric blue."
General Information
Common Name
Cavansite
Species
Cavansite
Transparency
Transparent
Dispersion
Strength: Weak Fire
Refractive Index
1.542-1.551
Birefringence
0.009
Optic Character
Biaxial
Optic Sign
Positive
Polariscope Reaction
Doubly Refractive (DR)
Fluorescence
SWUV: Inert
LWUV: Inert
LWUV: Inert
Pleochroism
Dichroic, strong colorless and blue
Hardness
3-4
Specific Gravity
2.210-2.310
Toughness
Poor
Luster
Vitreous
Fracture
Conchoidal
Cleavage
Good, in one direction
Chemical Name
hydrated calcium vanadium silicate
Chemical Formula
Ca(VO)Si4O10.4H2O
Crystal System
Orthorhombic
Chemistry Classification
Silicate
Cavansite Colors
-
Blue
Countries of Origin
New Zealand; Unknown; United States of America; Brazil; Iceland; India