Ekanite is green to brown colored rare stone with chemical composition calcium thorium silicate.

Thorium is a highly radio active element and due to this element Ekanite is converted to metamict state. In metamict state Ekanite almost acts like amorphous. By applying heat at certain temperature the metamict state of Ekanite can be restored to crystalline state.

The main source for Ekanite is Sri Lanka and Canada.

Chemical Composition :

Calcium Thorium Silicate – ThCa2Si8O20

Classification / Type :

It is a metamict mineral.

Crystal System / Forms :

Tetragonal System / Prismatic crystals and water-worn pebbles.

Cuts & Uses :

Facetted, cabochon, etc.

Hardness : 6 - 6.5
Lustre : Vitreous.
Magnification :

Crystalline inclusions.

Optic Character :

Anisotropic, D.R.; Uniaxial negative. Is almost amorphous and appears Isotropic (S.R.) due to metamict state.

Pleochroism : Not common.
Refractive Index / Birefringence :
  • Metamict: 1.597
  • Crystalline: 1.568 – 1.580 / 0.012

Simulants (with separation tests) :

Moldavite (R.I., S.G., inclusions), Brazilianite (optic figure, R.I., birefringence).

Sources :

Sri Lanka, Canada.

Specific Tests :

Highly radioactive.

Spectrum :

Not characteristic.

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