Metamorphic Rocks are igneous or sedimentary rocks that have been transformed by chemical, pressure, heat, and the presence if hot fluids. Metamorphic rocks are recognized by their often wavy and layered patterns, their hardness, and their minerals. The handbook for prospectors list 4 kinds of rock that are valuable or of interest. They are:
- Gneiss – these are coarsely banded rocks, typically light and dark. Feldspar and quartz are generally the lighter colored
- Schist- as layers become narrower and more readily separated gneiss grades into schist. Gneiss and schist both yield many mineral byproducts including metallic and non-metallic
- Quartzite – true quartzite is probably the most durable rock known it occurs wit gold, copper, lead, zinc, and iron, and manganese
- Slate – the metamorphism of shale yields slate. Slate is often found with gold.