Gemstones, defined by fact.
A vendor-neutral reference to every stone — documented by hardness, composition, colour and origin, and cross-linked to the gems it relates to.
Know the stone, not the sales pitch
Properties & hardness
Mohs hardness, chemical composition, crystal system, refractive index and colour cause — the measurable facts, laid out in clean tables.
Meaning & lore
The history, symbolism and folklore behind each stone — clearly separated from the science, never dressed up as medical fact.
Birthstones & buying
Which stone belongs to which month, natural versus treated, and what actually drives value before you spend.
Featured gemstones
Sapphire
Corundum in every colour but red — famed for its blue, and prized for durability.
Pearl
An organic gem grown by molluscs — soft, lustrous nacre requiring gentle care.
Peridot
August's vivid green birthstone — gem olivine coloured by its own iron content.
Ruby
The red variety of corundum — second only to diamond in hardness, and coloured by chromium.
Topaz
A hard aluminium fluorosilicate spanning colourless to imperial orange — with a notable cleavage to respect.
Turquoise
A sky-blue copper phosphate valued for millennia — soft, porous and often stabilised.
Gem families
The birthstone calendar
The traditional birthstone for every month, each linked to its full profile.
Start with a stone
From diamond to opal — open any gem for its hardness, composition, colour, meaning and the stones it relates to.
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