How Do You Identify Types Of Rocks?
The key to identifying rocks is first to identify the minerals that compose them. Geologists and students should begin with the most obvious type of rock. Follow these steps to help you identify types of rocks using a number of methods. Look at your rock to see if it has a metallic or non-metallic luster. Common metallic minerals include sulfides, oxides or a metallic element. Determine your rock’s density. Most rocks with a metallic luster also are high in density. Few non-metallic minerals have high density. Barite and sphalerite are the most common high density non-metallic minerals. Inspect your rock for its degree of hardness. If you can scratch glass with your rock, and it’s metallic, consider oxides. If it’s non-metallic and scratches glass, suspect such common minerals as quartz, feldspar or a silicate. If you can scratch your rock easily with a knife, suspect common sulfates, carbonates or halides. Examine your rock for its particular cleavage. Of the many different types of c
