THE GEMHOOD LIBRARY
Gemstone encyclopedia
Learn about remarkable natural stones through factual guides, care advice, and their cultural and historical significance.
Hematite
An iron-oxide mineral known for its metallic grey appearance and red-brown streak.
Read guide → Jadeite / NephriteJade
A jewellery and carving term referring chiefly to jadeite and nephrite, two distinct mineral materials.
Read guide → Aluminium silicateKyanite
An aluminium silicate mineral, often blue, whose hardness differs by crystal direction.
Read guide → FeldsparLabradorite
A feldspar that may display colourful iridescent flashes known as labradorescence.
Read guide → Rock dominated by lazuriteLapis Lazuli
A blue metamorphic rock traditionally used for decorative stones and jewellery, often with golden pyrite flecks.
Read guide → Copper carbonateMalachite
A strongly banded green copper carbonate mineral, polished for decorative gems; avoid abrasive cleaning.
Read guide → FeldsparMoonstone
Moonstone is a feldspar gemstone associated with a floating glow called adularescence in certain specimens. Jewellery settings often emphasise this optical effect. It is softer tha...
Read guide → Volcanic glassObsidian
Natural volcanic glass that forms when lava cools rapidly, often polished to a dark reflective finish.
Read guide → ChalcedonyOnyx
A variety of chalcedony often used in black or black-and-white jewellery; dyed material should be disclosed.
Read guide → Hydrated silicaOpal
Many opals display changing flashes of colour known as play-of-colour, while other varieties are more uniform. Their relatively modest hardness means that jewellery design, water e...
Read guide → Biogenic calcium carbonatePearl
An organic gem formed within certain molluscs; natural and cultured pearls must be accurately distinguished.
Read guide → OlivinePeridot
Peridot is the gem variety of olivine, commonly recognised by its yellow-green to green appearance. It brings a bright accent to earrings, pendants and bracelets. Because it is les...
Read guide → Manganese carbonateRhodochrosite
A manganese carbonate mineral with pink and red banding, most often made into protected jewellery.
Read guide → Manganese silicateRhodonite
A pink manganese silicate commonly containing distinctive black manganese-oxide veins.
Read guide → Quartz (SiO₂)Rose Quartz
A typically translucent pink variety of quartz; its soft appearance makes it popular in jewellery and carvings.
Read guide → Corundum (Al₂O₃)Ruby
Ruby is the red variety of corundum. Its rich red appearance makes it a recognised choice for statement rings, pendants and special-occasion jewellery. Hardness helps explain its r...
Read guide → Corundum (Al₂O₃)Sapphire
Sapphire is a gem variety of corundum, often associated with blue but also found in other colours. Its hardness makes it an enduring jewellery material, although the security of a...
Read guide → Banded chalcedonySardonyx
Discover its jewellery history, colours and traditional symbolism.
Read guide →Traditional and spiritual associations are presented for cultural interest, not as medical facts.