Zircon, native gold, copper and iron. Gold concentrate. Brazil
Rounded to subhedral zircon (grey) is accompanied by irregular-shaped high fineness gold (~960) (yellow, high reflectance) grains. Copper metal (pink, high reflectance, centre) and iron (white, high reflectance, top left) are rounded and are adventitious. Blue-grey areas are relict carbon-coating. Black areas are a polishing pit and an erupted air bubble in the resin (bottom left).
Grain mount, plane polarized light, x 80, air