Soapstone

Talc

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

Soapstone, also known as steatite, refers to compact masses of talc and other minerals known for their soapy or greasy texture. Due to its softness, it has been used since ancient times for carvings, ornaments and utensils.

General Information

Common Name
Soapstone
Species
Talc
Transparency
Opaque-Semitranslucent
Dispersion
Strength: None
Refractive Index
1.540-1.590
Tolerance:(+0.010/-0.002)
Birefringence
0.046- 0.050
Optic Character
Biaxial
Optic Sign
Negative
Polariscope Reaction
Aggregate (AGG)
Fluorescence
SWUV: Inert to yellow, pink or greenish
LWUV: Inert to weak pink, yellow or greenish yellow
CCF Reaction
None
Pleochroism
None
Hardness
1-2.5
Streak
White
Specific Gravity
2.200-2.800 Typical:2.750
Toughness
Poor
Inclusions
Soapstone is often veined or mottled in appearance and are greasy or soapy to touch. Stones are very soft can be scratched with a fingernail and might show surface damage.
Luster
Waxy, Dull, Pearly, Greasy
Fracture
Uneven
Cleavage
Perfect, in one direction
Chemical Name
magnesium silicate hydroxide
Chemical Formula
Mg3Si4O10(OH)2
Crystal System
Monoclinic
Chemistry Classification
Silicate

Soapstone Colors

  • Brown Soapstone
    Brown
  • Colorless Soapstone
    Colorless
  • Gray Soapstone
    Gray
  • Green Soapstone
    Green
  • Multi-color Soapstone
    Multi-color
  • White Soapstone
    White
  • Yellow Soapstone
    Yellow

Alternate Names

Steatite, Talc, Saponite

Countries of Origin

Russian Federation; Czechia; United States of America; Madagascar; Kenya; United Kingdom of Great Britain and Northern Ireland; Portugal; India; New Zealand; Canada; Austria; Unknown; Norway; China; Finland; Brazil; Poland; Italy; Australia; France; Lithuania; Germany

Care

Soapstone is easily scratched. If the soapstone has been heated it can obtain a mohs hardness between 5.5-6.5.