Key Points in this Chapter

KEY POINTS IN THIS CHAPTER

• Minerals must satisfy certain criteria to be called minerals. They must be inorganic.

• Minerals form a specific crystalline shape, based on their chemistry.

• Minerals have specific identifiers, such as color, density, hardness, luster, and cleavage.

• The Mohs hardness scale is used to tell the hardness of minerals in the field. It is a linear scale from 1 to 10, with 10 being attributed to diamonds.

• Minerals are either silicates or nonsilicates. Silicates are more common and are made from some combination of silicon and oxygen in tetrahedral shape.

• Nonsilicate materials occur in many kinds, mostly as salts of varying kinds. Ores are made from metals and are used to extract many precious metals.