Blue gemstones, sorted A–Z
Stone Mohs hardness Variety of
Aquamarine 7.5–8 beryl
Beryl 7.5–8
Iolite 7–7.5 cordierite
Labradorite 6–6.5 plagioclase feldspar
Lapis Lazuli 5–6
Larimar 4.5–5 pectolite
Moonstone 6–6.5 orthoclase feldspar
Sapphire 9 corundum
Spinel 8
Tanzanite 6–7 zoisite
Topaz 8
Tourmaline 7–7.5
Turquoise 5–6
Zircon 6–7.5