I put these two together because they both have been called by the common name Fool's Gold. The sun shaped rock is pyrite on top of slabbed shale. It comes from coal mines in Illinois. At one time these pyrite suns were thought to be fossils but the prevailing idea now is they are concretions spread out under pressure and forced to grow outward along a seam in the shale. Hardness is 6-6.5. The polished ball shaped mineral came from United Verde Mine in Jerome, Arizona. It is chalcopyrite (the buttery gold veining) in a matrix of black chlorite shist. Chalcopyrite, as the name implies, is a combination of pyrite and copper. Hardness of 3.5.
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