Metals like bronze (an alloy of Cu and Zn) and Iron have played a big role in civilization - hence the Bronze Age and Iron Age. The abundance of the.
1) Elemental Form e.g. Ag, Au, Pt – noble metals. 2) Aluminosilicates and Silicates Metal + Al, Si, O e.g. Beryl = Be 3 Al 2 Si 6 O 18 Hard to extract.