Gemmology

Essential qualities of a gem material 

               

  1. Beauty

o   Colour

o   Clarity

 2 .  Rarity

Stones with special optical effects

Chatoyancy - Cat's eye

Asterism - Star sapphire

Play of colour - Opal

Adulresecence - Moonstone

Labradorecence - Labradorite 

 3. Durability/ Hardness

Classification of gem materials 

• Minerals - inorganic origin 
• organic gem materials
• Man made products