Thomsonite | Gemopedia

Named for Thomas Thomson, a Scottish chemist, thomsonite is a mineral in the zeolite group. Ranging from translucent to opaque in appearance, it is found in various colors including brown, yellow, orange, pink, green, white and gray. Most famous for its nodular aggregates that exhibit a radial pattern, thomsonite may be found in various global locations, including Canada, the Czech Republic, Germany, Greenland, Scotland and the United States.
Alternate
Names
Gibsonite, Lintonite, Ozarkite
Colors
Brown, Yellow, Orange, Pink, Green, White, Gray

Thomsonite Classification

Common Name

Thomsonite

Species

Thomsonite

Variety

Colors

Brown, Yellow, Orange, Pink, Green, White, Gray

Alternate Names

Gibsonite, Lintonite, Ozarkite

Gemstone Groups

Key Separations

Comments

Gibsonite is the fibrous pink version of thomsonite from Scotland. Lintonite is the translucent green variety of thomsonite for the Lake Superior region. Ozarkite is the white variety of thomsonite from the Magnet Cove region of Arkansas. Misnomer: Lake Superior agate

Thomsonite Optical Properties

Transparency

Translucent - Opaque

Refractive Index

1.515-1.54
Tolerance:(+0.015/-0.018)

Birefringence

0.025

Optic Character

Biaxial

Optic Sign

Positive

Polariscope Reaction

Aggregate (AGG)

Fluorescence

SWUV: Inert
LWUV: Inert to weak white

CCF Reaction

Pleochroism

Unobservable

Dispersion

Comments

Thomsonite Chemistry & Crystallography

Chemical Name

Chemical Formula

NaCa2Al5Si5O20-6H2O

Synthesis

Crystal System

Orthorhombic

Classification

Silicate

Nature

Natural

Crystallinity

Polycrystalline

Comments

Thomsonite Characteristic Physical Properties

Hardness

5-5.5

Streak

Specific Gravity

2.2-2.4 Typical:2.35

Toughness

Fair

Inclusions

Thomsonite has a radial fibrous structure that gives an eye ball like appearance and looks similar to agate.

Luster

Vitreous

Stability

Fracture

Uneven

Cleavage

Perfect, in one direction

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