aggregate
aluminium
blue
botryoidal
cluster
crystal
crystalline
cyanite
gem
gemstone
geological
geology
goethite
healing
hydrothermal
iridescent
iron
kyanite
matrix
metallic
mine
mineral
mineralogy
natural
ore
oxide
pegmatite
precious
pyrite
rock
sample
science
silicate
specimen
sphere
spheres
stone
structure
sulphide
therapy
translucent
uncommon