Light Blue Crystals

Subtle agate variety; lacy bands of blue, white, and grey; coloured layers consist of micro-crystals of quartz; forms in geodes within volcanic rock

Used in making ceramics, glass, flares, and fireworks; often forms at high temps in granite and pegmatite; crystallizes from evaporation of salt water; clusters are more common than individuals crystals

AKA anhydrite; common sedimentary mineral that forms massive layers of rock; created when gypsum loses water; can also occur from evaporation of sea water or weathering of pyrite; named after Angela - the partner of the person who discovered the stone

A main component of human tooth enamel; crystals have a 'crackled' appearance underneath smooth surfaces; name derives from the Greek word 'Apate' meaning "deceiver"

Discovered in 1967 in the Merelani Hills near Mount Kilimanjaro in Tanzania; rare variety of the mineral zoisite; has pleochroism of red, blue, and brown; blue colouring is deepened by heating