Fluorite – a frozen rainbow

Fluorite is like a rock-collector's psychedelic dream, because it's found in a rainbow of colours from red to deep purple. …

Amethyst

Did I ever tell you that I love rocks? How did you guess? I'm taking a closer …

Britain’s oldest rocks

Lewisian gneiss is the oldest type of rock found in Britain, but there's plenty of it, especially in the Western …