Air bubbles

Native gold and platinum-iron alloy. Kalimantan, Indonesia

Pentlandite, pyrrhotite, pyrite and chalcopyrite. Bushveld, Republic of South Africa


Anisotropy

Heazlewoodite, millerite and nickel arsenide. Unst, Shetland Islands, Britain

Marcasite. Ashover, South Pennines, Britain

Sphalerite, pyrite and chalcopyrite. Bayda, Oman

Tellurobismutite and hessite. Clogau Mine, Wales, Britain


Bireflectance

Bornite and chalcocite. Gortdrum, Ireland

Bornite, covelline and sulphosalt. Levant Mine, Cornwall, Britain

Cassiterite and molybdenite. Glen Gairn, Scotland.

Cassiterite, thorite and zircon. Ririwai, Nigeria.

Ilmenite, TiO2-rich minerals and haematite. Derbyshire, Britain

Magnetite, molybdenite, pyrite and chalcopyrite. Newry, County Down, Britain

Molybdenite. Jersey, Channel Islands, Britain.

Rutile, wolframite, cassiterite and arsenopyrite. Mount Pleasant, New Brunswick, Canada

Stibnite. Bo Thong, Thailand.


Internal reflections

Altered magnetite and anatase. Derbyshire, Britain

Cassiterite, zircon and thorite. Ririwai, Nigeria

Cassiterite. Botallack Mine, Cornwall, Britain

Cinnabar and pyrite. Mount Amiata, Italy

Columbite, rutile, zircon and xenotime. Ririwai, Nigeria

Limonite, haematite and magnetite. Hamersley Basin, Australia

Magnetite, molybdenite, pyrite and chalcopyrite. Newry, County Down, Britain

Pyrite, rutile, columbite and zircon. Ririwai, Nigeria

Rutile. Richards Bay, Republic of South Africa

Sphalerite, bournonite and galena. Navan, Ireland

Wolframite and cassiterite. Glen Gairn, Scotland


Oil droplets

Bornite, chalcopyrite and chalcocite. Jersey, Channel Islands. Britain



Reflection pleochroism

Bornite, covelline and sulphosalt. Levant Mine, Cornwall, Britain

Bornite, magnetite, chalcopyrite. Palabora, Republic of South Africa

Cassiterite and molybdenite. Glen Gairn, Scotland

Chalcopyrite, pyrrhotite, cubanite and pentlandite. Stillwater. Montana, USA

Chalcopyrite, pyrrhotite, pentlandite, and cubanite. Stillwater, Montana, USA

Cubanite, chalcopyrite. Bushveld, Republic of South Africa

Haemoilmenite and rutile. Allard Lake, Quebec, Canada

Ilmenite, TiO2-rich minerals and haematite. Derbyshire, Britain

Ilmenite. Glen Gairn, Scotland

Magnetite, molybdenite, pyrite and chalcopyrite. Newry, County Down, Britain

Molybdenite. Jersey, Channel Islands, Britain

Pyrite, chalcopyrite and covelline. El Salvador, Chile

Pyrite, marcasite. Mount Pleasant, New Brunswick, Canada

Stibnite. Bo Thong, Thailand


Relief

Bornite, stromeyerite, chalcocite, pyrite and tetrahedrite group mineral. Unknown Provenance