Gemstones

A gemstone, gem or also called precious or semi-precious stone is a highly attractive and valuable piece of mineral, which — when cut and polished — is used in jewelry or other adornments. However certain rocks, (such as lapis-lazuli) and organic materials (such as amber or jet) are strictly speaking not minerals, but are still applied in jewelry and adornments, and are therefore often considered to be gemstones as well. Some minerals that are too soft to be generally applied in jewelry may still be considered gemstones because of their remarkable color, lustre or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone.