Natural Gemstone
Any of various minerals highly prized for beauty, durability, and rarity. A few noncrystalline materials of organic origin

Organic Gemstones

Amber  | coral | ivory |  jet |  pearl

Hybrids

Assembled gem- cut jewel manufactured from two or three pieces of stone that are cemented together to create a larger stone with increased value.
 
Operations

Gems also are used as (good-luck charms). For birthstones

How to Care for Gemstones
 

Useful Web Sites

New York – The International Colored Gemstone Association (ICA) recently announced ... by some of the world’s biggest names in the gem and jewelry industry http://www.gemstone.org/index.html

Mineral Gemstones

Achroite | Alexandrite | Almandine | Amazonstone | Amethyst | Aquamarine | Asparagus Stone | Aventurine | Brazilian Emerald  |  Cape Emerald  | Cats-Eye | Chalcedony | chrysobery l Citrine | Cymophane  | demantoid | Diamond | emerald | Hessonite | Jade | Jasper | labradorite | Lapis Lazuli | Moonstone | Morganite Opal | Peridot | Peristerite | Phenakit  | Pyrope  | Rock Crystal | Rose Quartz | Ruby | Ruby Spinel | Sapphire | Smoky Quartz  | Spessartine | Sunstone | Tanzanite | Tigereye | Topaz |Transvaal Jade |
Turquoise | Uralian Emerald | Zircon