minerals

Minerals

Different rocks also have different shapes and textures. Some rocks are smooth, whereas others have jagged edges. Some rocks crumble in your hands, while others are so hard that you can use them to cut things. Scientists use these properties to classify, or tell apart, rocks. However, scientists also study what different rocks are made of.

Have you ever gone on a scavenger hunt to look for different rocks? How did you tell the rocks apart? You probably began with their appearance. Some rocks are dark in color, whereas others are so clear that you can almost see through them. Some rocks appear shiny when sunlight hits them, while others appear dull.

Minerals

Minerals are classified by properties

Rocks are made of minerals. Minerals are solid, inorganic substances that occur naturally in the topmost layer of Earth, or the crust. An inorganic substance is one that has never been alive. In other words, minerals are not made by humans. There are many different types of minerals, but each type has a unique composition. Each type of mineral is made of a particular combination of elements that form a unique crystalline structure. A crystalline structure is the arrangement of atoms in a repeating pattern of shapes.

Scientists classify minerals to make them easier to study

Minerals can be separated into groups based on their physical properties. Remember that a physical property is one that you can observe or measure without changing the matter itself. Some physical properties of minerals scientists study are:
● Luster (the way that light reflects off the surface of a mineral)
● Color
● Hardness
● Streak (the color left behind after scratching a mineral on a porcelain plate)