Are you curious about rocks and minerals? Why not make a science project out of it? When you do a project on rocks and minerals, you can explore an exciting world that spans from the depths of soil and caves to the heights of mountains and even outer space. So, grab your favorite rock samples and start your exploration today!
What is a rock?
A rock is made from different minerals stuck together by nature. The minerals in a rock might have been formed in the rock at different times, so a rock can be constantly changing. Some common rocks are limestone, sandstone, and granite.
What is a mineral?
Minerals are natural substances that are made up of one type of compound that's arranged in an orderly way. Each mineral looks different and has its own special properties that set it apart from others. Some examples of minerals are quartz, feldspar, mica, and calcite.
What is a crystal?
A crystal is a mineral with an orderly pattern of atoms, which is reflected in the geometric shape of the crystal as it grows larger. Differences in temperature and chemical composition cause variations, but crystals need ideal growing conditions and room to grow to show their geometric form. Most rocks are made up of many tiny mineral crystals, but large museum-quality crystals have room to grow uninhibited. Some common crystals are diamonds (carbon crystals), quartz (silicon dioxide crystals), pyrite (fool's gold, iron sulfide crystals) and salt (sodium chloride crystals).
What are the 3 types of rocks?
Sedimentary rocks
Sedimentary rocks are made from pieces of rocks or once-living things that pile up on the Earth's surface. Because of this, sedimentary rocks usually have layers, and some famous formations in the desert are made of sedimentary rocks. There are three main kinds of sedimentary rocks:
Clastic sedimentary rocks are formed from pieces of rocks that are cemented together. Some clastic sedimentary rock examples are sandstone, shale, siltstone and breccia.
Chemical sedimentary rocks are formed when dissolved substances precipitate out of the solution and become a solid. Some chemical sedimentary rock examples are rock salt, limestone, iron ore, flint, chert and some dolomites.
Biologic sedimentary rocks are formed when many living things die, and these rocks are often where fossils are found. Some examples of biologic sedimentary rock examples are coal, chalk, limestone, diatomite and some dolomites.
Metamorphic rocks
Metamorphic rocks are rocks that have been changed from their original form due to high heat, high pressure, and hot fluids. These conditions are found deep within the Earth or where tectonic plates meet. Metamorphism does not melt the rocks, but transforms them into denser, more compact rocks with new minerals.
Some common metamorphic rocks include:
marble - changed from limestone
quartzite - changed from sandstone
slate, phyllite, schist and gneiss - changed from mudrock
granite gneiss - changed from granite
chlorite schist and amphibolite - changed from basalt
Igneous rocks
Igneous rocks form when hot, melted rock cools and hardens. There are two types, intrusive and extrusive.
Intrusive igneous rock
Intrusive rocks cool slowly below the Earth's surface and have large mineral grains. Since intrusive rocks are made inside the earth, they are also called plutonic rocks, named after Pluto, the Greek god of the underworld. Some common intrusive igneous rocks are granite, peridotite, pegmatite, diabase, diorite and gabbro.
Extrusive igneous rock
Extrusive rocks cool quickly on the surface and have small mineral grains or even a glassy texture. Volcanic eruptions produce extrusive rocks, and magma trapped deep in the Earth produces intrusive rocks. Extrusive rocks are also called volcanic rocks because they are formed by volcanic activity, named after Vulcan, the Roman god of fire. Some common extrusive igneous rocks are pumice, basalt, obsidian, rhyolite, dacite, andesite, tuff and scoria.
The Rock Cycle
The rock cycle is the process of how rocks can form and change over time. Different types of rocks form in different environments, such as when molten rock cools underground to form an igneous rock or when rocks are exposed to heat and pressure to form metamorphic rocks. When rocks are exposed to weathering and erosion, they can break down into smaller pieces and become part of sedimentary rocks. The rock cycle is an important process that shapes the Earth's surface over millions of years and can take many paths depending on the environment's conditions.
What kinds of rock projects are there?
We have rock projects where you'll learn all about different rocks and minerals, the fascinating process of how rocks are formed and broken down over time through the rock cycle, and even get to make your own beautiful crystals! And if that's not enough, delve into the past by studying fossils and uncovering the secrets of the amazing animals and plants that once roamed the earth. Get ready for an adventure with rocks!
rock collection: categorizing rocks (from soil), testing properties of rock samples (hardness, density, porosity), finding tiny space rocks (micrometeorites).
modeling the rock cycle: sedimentary, metamorphic and igneous rocks, magma (with a Pet Rock, chocolates, Starbursts or crayons)
exploring ways rocks are made and broken down: erosion (mountain, soil), eruptions (volcano)
making crystals (sugar, salt, borax), fossils, stalactites and stalagmites
