Beryls are beryllium-aluminium-silicates. As pure beryl, they are colourless, but coloration is derived from impurities - into green, yellow, pink or blue. Iron colours beryl into Blue- the most beautiful sea-blue Aquamarine.

Traces of iron, and minerals containing uranium, give a colourless beryl an intense yellow tone - the Golden beryl.

ome Beryls display a Cats-eye effect and are a collector gem.