Gemstones and Minerals

01 What are minerals?
Except for a few layers of top soils on the surface, much of the Earth is made up of solid materials called rocks. These soils and rocks are products of minerals: the basic units of rocks. Mineralogy defines “minerals” as:

1.    Naturally occurring homogenized solids.
2.    Products of inorganic reactions.
3.    Has a specific chemical structure.
4.    Has a defined atomic arrangement.




02 What are gemstones?
Over 90% of gemstones are refined from naturally occurring minerals, formed via inorganic processes; the remaining 10% are organic gemstones, non-mineral material such as pearl, amber, coral and ivory, which are formed in living organisms. Although more than 4,000 types of minerals have been identified, less than 100 minerals can be refined into gemstones. Of these 100 types, only 20 types or so are gemstone-grade and traded on the international gemstone market.

Aquamarine Aquamarine


03 Criteria for gemstone-grade minerals 
Gemstone-grade minerals are mineral crystals that have been artificially cut and refined into collectible items and precious jewelry. A mineral deemed worthy of gemstone quality must fulfill the following 3 conditions:

1.    Beauty – gemstones should have bright colors, clean luster, and few imperfections; or possess unusual optical or physical phenomena such as asterism, chatoyancy, and color change.
2.    Rarity – the more rare the gemstone is in nature, the higher its value.
3.    Durability – the harder the gemstones the more resistant they are to damage. Gemstones are usually ranked 6 or above on the Mohs scale of mineral hardness; precious gemstones can even be ranked 7 and above. Moreover, to last indefinitely, gemstones should be chemically and physically stable to resist corrosion from acids and bases, and have no visible cleavages and fractures.

Cat's eye tourmaline Tourmaline



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