Sillimanite is an aluminum silicate, related to both andalusite and kyanite. In fact these three minerals are polymorphs - they share the same chemical composition but different crystal structures.

Sillimanite is named after the American chemist Benjamin Silliman (1779-1864). Silliman was one of the first American professors of science and taught at Yale University.

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Buy Cat's Eye Sillimanite Gems

2.51ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 7.9 x 7.1mm, Natural untreated Gemstone, Translucent Clarity, 1 piece Sillimanite Cat's Eye in Warm White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

0.73ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 6.6 x 4.6mm, Transparent Clarity, Natural untreated gemstone, 1pc Sillimanite Cat's Eye in Clear Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

0.92ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 6.6 x 4.6mm, Transparent Clarity, Natural untreated gemstone, 1pc Sillimanite Cat's Eye in Warm White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7 x 4.7mm Oval White Sillimanite Cat's Eye from Madagascar, Weight of 1.04ct, Natural untreated Gemstone in Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye - Color: Translucent White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7.2 x 5.1mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 1.02ct, Natural untreated gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - the Color is Warm White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

6.5 x 4.9mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 0.82ct, Natural untreated Gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - Color: Clear, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

6.3 x 5.9mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 1.33ct, Natural untreated Gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - Color: Warm White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7.1 x 5.7mm Oval White Sillimanite Cat's Eye from Madagascar, Weight of 1.38ct, Natural untreated Gemstone in Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye - Color: White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

1.05ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 6.1 x 5.8mm, Natural untreated Gemstone, Transparent Clarity, 1 piece Sillimanite Cat's Eye in Clear White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

1.84ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 7.7 x 5.8mm, Natural untreated Gemstone, Translucent Clarity, 1 piece Sillimanite Cat's Eye in Warm White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

6.3 x 5.9mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 1.14ct, Natural untreated Gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - Color: Clear White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7 x 5.4mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 0.83ct, Natural untreated gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - the Color is Clear White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7.4 x 5.1mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 1.1ct, Natural untreated Gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - Color: White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

1.26ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 7.1 x 5.2mm, Natural untreated Gemstone, Transparent Clarity, 1 piece Sillimanite Cat's Eye in White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7 x 4.5mm Oval White Sillimanite Cat's Eye from Madagascar, Weight of 0.83ct, Natural untreated Gemstone in Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye - Color: Clear White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7.5 x 4.8mm Oval White Sillimanite Cat's Eye from Madagascar, Weight of 1.34ct, Natural untreated Gemstone in Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye - Color: White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

6.6 x 4.5mm Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Weight of 0.99ct, Natural untreated gemstone in Transparent Clarity, 1pc Sillimanite Cat's Eye - the Color is Clear White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

7.2 x 4.2mm Oval White Sillimanite Cat's Eye from Madagascar, Weight of 1.24ct, Natural untreated Gemstone in Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye - Color: Clear White, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

1.25ct Oval Clear White Sillimanite Cat's Eye from Madagascar, Dimension 7.6 x 5.2mm, Natural untreated Gemstone, Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

0.88ct Oval Cabochon White Sillimanite Cat's Eye from Madagascar, Dimension 6.9 x 5.1mm, Natural untreated Gemstone, Transparent Clarity, 1 piece Sillimanite Cat's Eye in Clear White Color, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

1.61ct Oval Clear Sillimanite Cat's Eye from Madagascar, Dimension 6.7 x 5.4mm, Natural untreated Gemstone, Transparent Clarity, 1pc Oval Cabochon Sillimanite Cat's Eye, Mohs Hardness of 6.5 - 7.5 suitable for daily wear jewelry

Cat's Eye Sillimanite

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