Heazlewoodite, pentlandite, magnetite an native copper. Unst, Shetland Islands, Britain
Heazlewoodite (white, top) is intergrown with pentlandite (brown, with cleavage, centre) and rounded magnetite (light brown-grey, left) crystals, in a dunite. Minor amounts of magnetite also occur along fractures within pentlandite (bottom left, bottom centre) as a very characteristic intergrowth. Trace amounts of native copper (centre left) within magnetite are present but have tarnished to an orange colour. Dark grey areas are secondary silicates.
Polished thin section, plane polarized light, x 80, air