Apophyllite 13.08 ct.

Apophyllite

A popular mineral among collectors who has been recently re-considered : check

http://www.mindat.org/min-283.html

Is a Hydrated Potassium Calcium Sodium Silicate Fluoride Hydroxide with formula

(K,Na)Ca4Si8O20(F,OH) - 8H2O .

Although is quite common in natural crystal, is very difficult to cut and polish, due to his easy cleavage: a challenge for the cutters.

The hardness is 4.5-5 and this gem here comes from a classic locality: Poona,India.

A very small flaw is visible at naked eye

Size: 14.9x14.5x11.3 mm

Weight: 13.08 ct.

CODE#6840