Witherite | Gemopedia

This gem was named in 1790 for William Withering, the English physician and naturalist that first described the mineral. This mineral is rarely faceted due to the scarcity of gem-quality rough and also because witherite dust (a primary component of rat poison) is toxic if inhaled. Cut gems are very small and are typically white or colorless.
Colors
Yellowish-White, Pale Green To Colorless

Witherite Classification

Common Name

Witherite

Species

Witherite

Variety

Colors

Yellowish-White, Pale Green To Colorless

Alternate Names

Gemstone Groups

Aragonite

Key Separations

RI and appearance.

Comments

Witherite dust is toxic if inhaled and always wash your hands after handling. Stones are always twinned.

Witherite Optical Properties

Transparency

Transparent - Opaque

Refractive Index

1.529-1.677

Birefringence

0.148

Optic Character

Biaxial

Optic Sign

Negative

Polariscope Reaction

Doubly Refractive (DR)

Fluorescence

SWUV: Moderate bluish white or violet
LWUV: Strong bluish white

CCF Reaction

Pleochroism

Unobservable

Dispersion

Strength: weak fire

Comments

Witherite Chemistry & Crystallography

Chemical Name

barium carbonate

Chemical Formula

BaCO3

Synthesis

Crystal System

Orthorhombic

Classification

Carbonate

Nature

Natural

Crystallinity

Crystalline

Comments

Witherite Characteristic Physical Properties

Hardness

3-3.5

Streak

White

Specific Gravity

4.27-4.79

Toughness

Poor

Inclusions

Witherite has a sleepy appearance.

Luster

Vitreous

Stability

Poor

Fracture

Uneven

Cleavage

Good, in one direction, Poor, in two directions

Comments

JTV on Google+
0 Items
My Wish List
Close
Item
Description
Qty.
Price


Estimated Order Total:
0
Total Due Today:
0
Close
Item
Description
Qty.
Price


Page of 1