Braggite almost never occurs with any crystal faces, typically occurring only
as microscopic grains in sulfides (though usually in contact with a silicate
mineral at some point, as well). These, however, are unusually good examples
in that they are sizeable and fairly obvious to the naked eye in contrasting
chalcopyrite and
pyrrhotite-infused bronzite and
plagioclase matrix. Often the grains are highly shattered and present no
fracture surfaces, or have even worse altered; but these present nice lustrous
fracture surfaces.
Origin: Stillwater Mine, Nye, Montana, U.S.A.
Sample size: 2-4 cm
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