Hydrated silica with water still in it — the water is why it plays colour, and why it is treated gently.
Stones
What the studio works with, by family — what it is, how it behaves, and how to look after it. Each opens into its own page.
Chalcedony — quartz grown too fine to see the crystals. Hard-wearing and safe for every day.
Hardness seven — the working definition of an everyday stone. The coloured varieties rest out of the sun.
Corundum, hardness nine — nothing but diamond scratches it. Ruby is the red; sapphire is everything else.
Beryl coloured by iron, glassy and clean. Small stones stay the colour of shallow water.
Feldspar with a sheen that floats above the surface.
Hardness ten — the hardest thing that will ever be in this studio.
Always green, only green — one of the few gems formed in the mantle rather than the crust.
Honest colour, hardness eight, and a long history of being mistaken for ruby.
The widest colour range of any gem species — often two or three colours in one crystal.
Nacre laid down by a living animal. Soft by mineral standards, and treated accordingly.