Colourless/Clear Crystals

AKA rock crystal; first stone to be described as crystal; Greeks called the rock 'crystalos' meaning "permanent ice"; constitutes more than 1/10 of Earths crust; prized by healers and shamans

Common mineral found within volcanic rock cavities; crystals are commonly needle-shaped, columnar, or tabular - often with four sides meeting at a pyramidal point; shiny surface; sensitive to heat; has a green variety called fluorapophyllite

Rare yet fairly wide distributed mineral of dolomite deposits; derived name from Danbury, Connecticut, USA; crystals are usually slender and chisel-tipped; large crystals have a frosty sparkle; occasionally golden or pink in colour

Carbon; hardest natural mineral known; very popular in expensive jewelry; name included in a song title by Shirley Bassey (used for a theme song for the 007 film back in 1971)

Forms in sedimentary borax deposits in salt lake basins and arid desserts; can form aggregates of needle-like crystal, fibrous aggregates, granules, and massive varieties; aka "TV stone"; soft mineral; sensitive to humidity and water

Occurs as pyramidal or prismatic crystals within igneous rocks; resistant to erosion; sometimes used as an imitation stone; heat-treated to turn to a variety of colours; gem-quality stones usually come from Australia