Hackmanite mineral specimens

Hackmanite is an extremely rare form of Sodalite which demonstrates tenebrescence; the changing of colour when exposed to sunlight.

In most cases, the mineral is purple when originally mined, and fades to colourless when exposed to sunlight. This can be reversed by leaving the specimen in a dark place for some time - sometimes up to a month.

Specimens from Afghanistan and Pakistan, however, retain their purple colouring constantly - until left in the dark for an extended period, at which point they can fade to colourless.

Our current stock includes:

• Various sized specimens from the Pakistan Afghanistan border - these are a pale white-purple in dark areas, a light purple in daylight and become a darker purple after exposure to bright UV light. They should then fade when kept in a dark place again.