Grenades are a large group of similar stones, which some classify as ornamental, others to the noble ones. Chemically, they belong to the silicates in the general formula M.3R2 (SiO4)3. Interesting real construction …
Tag: korund
Rubin i szafir
Rubin i szafir – Korund.
Transparent types of corundum are precious gemstones, have been used for ornamental purposes for a very long time. The red variety is called ruby, blue or other - sapphire. Fine crystalline, compact, granular varieties of corundum are used for the purpose …
Diamond imitations
Diamond imitations
Apart from the primitive way of imitating diamonds with varieties of glass with a high refractive index, colorless sapphires are used to imitate this most valued gemstone., zircons or topazes, sometimes also transparent quartz (Mountain crystal).
A very large factor …