Rocks You Should Know

Although you are able to classify a rock by testing its properties, it is also helpful to be familiar with which major rocks belong to which families.

The rocks you should always remember are sedimentary are shale, siltstone, sandstone, and conglomerate.

The rocks you should always remember are metamorphic are slate, phyllite, schist, gneiss, hornfels, quartzite, and marble.

The rocks you should always remember are igneous are rhyolite, granite, pegmatite, basalt, and gabbro.

In case you did want to test the rocks, they are different thing to look for in each rock family. Sedimentary rocks are classified by texture (clastic, crystalline, or bioclastic). Metamorphic rocks are also classified by texture (foliated or nonfoliated). Igneous rocks are classified by grain size (extrusive or intrusive) and color (felsic or mafic).