<p>Sperrylite (silver-colored) in platinum-copper ore (field of view 5.7 cm across) with chalcopyrite (brassy gold) &amp; magnetite (black).
</p><p>Geology &amp; Age: massive Fe-Cu sulfide hosted in gabbrodolerite, lower series of differentiated layered igneous intrusion associated with hotspot-generated Siberian Traps Flood Basalts, Permian-Triassic boundary time, 251 my.
</p><p>Locality: apparently from the Oktyabersky Mine, ~12 km NW of Talnakh, Norilsk Mining District, Putoran Plateau, Krasnoyarsk Territory, northern Siberia, Russia.
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<hr><p>Sperrylite is a very rare platinum arsenide mineral (PtAs2).  Very few localities on Earth have been reported to have sperrylite.  The two classic localities for this mineral are Sudbury, Ontario, Canada and the Norilsk Mining District in northern Siberia.
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Sperrylite has a metallic luster, a bright silvery color, a dark gray to black streak, is fairly hard (H = 6 to 7), and is quite heavy for its size.  It forms crystals in the isometric system, resulting in octahedrons and octahedrons truncated by cubic forms.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/47445767@N05">James St. John</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/jsjgeology/15124019805/">Sperrylite in platinum-copper ore (Permian-Triassic boundary time, 251 Ma; Norilsk Mining District, Krasnoyarsk, northern Siberia, Russia) 2</a>