Wulfenite
Wulfenite
Published: June 2014
Modified: January 2022
Known for its striking orange, yellow, and red hues, nice luster, and unique crystal habits, wulfenite is a lead molybdate that is found in the oxidation zone of lead-ore deposits. Wulfenite typically forms thin, tabular crystals. Finding a crystal thick enough to fashion into a gem is challenging.
General Information
Common Name
Wulfenite
Species
Wulfenite
Transparency
Transparent - Translucent
Dispersion
Strength: Strong Fire Value: 0.203
Refractive Index
Over The Limit 2.280-2.400
Birefringence
0.12-0.122
Optic Character
Uniaxial
Optic Sign
Negative
Polariscope Reaction
Aggregate (AGG), Doubly Refractive (DR)
Fluorescence
SWUV: Inert to weak yellow, orange or red
LWUV: Inert to weak red
LWUV: Inert to weak red
Pleochroism
Unobservable
Hardness
3
Streak
White
Specific Gravity
6.500-7.000
Toughness
Poor
Luster
Adamantine, Resinous
Fracture
Uneven, Subconchoidal
Cleavage
Good, in one direction, Poor, in two directions
Chemical Name
lead molybdate
Chemical Formula
PbMoO4
Crystal System
Tetragonal
Wulfenite Colors
-
Brown -
Orange -
Brown -
Red -
Green -
Colorless -
Gray -
White -
Black
Countries of Origin
Unknown; Namibia; United States of America; Mexico
Care
Very soft , careful handling