Have you ever wondered about the shiny, sparkly, and colorful things you sometimes find on the ground? Those are minerals, amazing treasures that come from deep within the Earth. Let’s embark on a journey to discover what minerals are, how they differ from rocks, their special characteristics, and some of the incredible types of minerals!
What Are Minerals?
The Earth is made up of thousands of different minerals. Minerals are like nature’s gemstones – they’re tiny pieces of the Earth that are so precious and unique. You can think of them as the building blocks of rocks. Just like how LEGO bricks come in different shapes and colors, minerals are like the colorful, tiny pieces that make up bigger things called rocks.
Minerals are solid substances that occur naturally. They can be made from a single element (like gold or copper) or from a combination of elements.
Rocks vs. Minerals
Imagine you have a batch of cookies. The cookies are like rocks, and the ingredients used to make them, like flour, sugar, and chocolate chips, are like minerals. So, rocks are made up of different minerals, just like cookies are made from different ingredients.
Minerals have a specific chemical structure which is the same throughout the entire mineral. Rocks, on the other hand, are composed of a variety of different minerals and are not consistent throughout their structure.
Characteristics of Minerals
A mineral has 5 characteristics: naturally occurring, solid, inorganic, crystalline structure, and the same chemical composition throughout.
- Solid – All minerals will be solids at normal temperatures on Earth.
- Naturally occurring – Minerals occur in nature. Solids that are made in a chemistry lab don’t count as minerals.
- Inorganic – Minerals don’t come from plants, animals, or other living organisms.
- Same chemical composition throughout – Specific minerals will always have the same chemical formula. They will have the same combination of elements.
- Minerals also generally are formed with a crystal structure.
Properties of Minerals
Minerals have special characteristics that make them special and different from each other:
– Color: Minerals come in all sorts of colors, like red, blue, green, and even shiny gold!
-Shape: Some minerals grow in cool shapes called crystals. Crystals can be pointy, like the tip of an icicle, or flat and shiny, like a mirror.
-Hardness: Some minerals are super hard, like a tough rock, while others are softer, like a piece of chalk.
-Luster: Luster is the way a rock or mineral reflects light. It is a physical attribute that can be easily observed. A mineral’s luster can be described as metallic, if it reflects light and non-metallic, if it does not. Some minerals shine like a bright light, while others might look more like a soft glow.
-Streak: If you rub a mineral against a rough surface, it leaves behind a mark called a streak. It might be the same color as the mineral, or it might surprise you and be a different color!
-Cleavage: Cleavage describes how a mineral breaks up into pieces. Some minerals break up into small cubes while others may break up into thin sheets.
Types of Minerals
Scientists can classify minerals into groups based on their chemical makeup. There are thousands of different minerals, only about 30 are common in Earth’s crust. These 30 minerals make up most rocks in the crust. They are called rock-forming minerals.
- Silicates are most common group. All the minerals in this group contain oxygen and silicon—the two most common elements in Earth’s crust—joined together. Silicates may include other elements such as aluminum, magnesium, iron and calcium. Quartz, feldspar, and mica are common silicates.
- Carbonates are the second most common group of rock-forming minerals is the carbonates. All the minerals in this group contain carbon and oxygen joined together. Calcite, which is common in seashells, is a carbonate mineral.
- Oxides include the minerals from which most metals, such as tin and copper, are refined. An oxide consists of an element, usually a metal, joined to oxygen.
- Sulphates commonly form in evaporites where highly salty waters slowly evaporate, allowing sulfates and halides to precipitate where the water evaporates. Sulphates also occur where hot waters are forced through the rock, as with geysers.
There are many other mineral groups. Exploring minerals is like going on a treasure hunt in your own backyard. Keep your eyes peeled for colorful rocks that might have hidden minerals inside them. The Earth has so many amazing secrets just waiting to be discovered, and minerals are some of its most dazzling treasures!