Materials

Materials that are used in jewelery in many colors and combinations:
Gold, Silver, Titanium, Stainless Steel, Gems, Cold Enamel, Stone, Glass, Plastics, Plexiglas, Rubber.

Gems: Most gems are minerals (for instance diamonds), others are mineral aggregates (lapis lazuli) or rock (Onyxmarble). Also some of organic origin (amber) to be considered precious. Coal, bones, glass and metal are also used as ornamental stones. Some stone is the color, the iridescence or sheen that distinguishes them from ordinary stones, others are special because of their great hardness or special inclusions. Also rarity plays a role in it apart from a stone or gem. Cameos do not exist; Except when they are sawed, half stones.

Gemstone species and crystals that I like to incorporate in jewelry, in the cabochon (smooth-sphere) or faceted diamond cuts:  Amethyst, Aquamarine, Quartz, Chrysoprase, Citrine, Diamond, Herkimer-diamond, Garnet, Jade, Lapis Lazuli, Moonstone, Onyx, Opal, Ruby, Sapphire, Amethyst, Sodalite, Spinel, Topaz.
 
Gemstones   wikipedia.org / wiki / Gemstones
Diamonds     wikipedia.org / wiki / Diamond
Runes info    wiki / Runes
runes             runemaker.com
 
Natural raw crystals used in jewelry. Ruby 2x, 1 Sapphire:

Diamond crystals.