This is a dark black rock with gold shimmering chunks sticking out of it, some of the chunks look rainbow colored or fake gold color it is a small rock less than 5 lbs (https://i.stack.imgur.com/YpNKm.png)enter image description hereenter image description here

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    $\begingroup$ The 'gold' chunks may be pyrite. Can you read this and improve your question? Especially, pictures with better lighting would be nice (daylight). $\endgroup$ – Jan Doggen Sep 19 '18 at 8:02

The rainbow colored/gold chunks may be the copper iron sulfide (CuFeS2) mineral chalcopyrite. The surface of chalcopyrite can lose it's gold color when weathered and turn a gray, green, red, or blue iridescent color depending on the specific weathering conditions involved. Chalcopyrite can be distinguished from pyrite (iron sulfide) by scratching it with a nail - chalcopyrite can be scratched by a nail whereas pyrite will not.

  • $\begingroup$ Yep. This is copper ore, with chalcopyrite. Maybe also bornite? Hard to see from this picture. $\endgroup$ – Gimelist Sep 20 '18 at 10:03

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