CLASSIFICATION IS IT A ROCK OR A MINERAL? BECOME A ROCK HOUND

Is it a rock or a mineral? Click each picture to find out. Two picture – rock and mineral. Link to slide with rock or mineral properties Click each picture to find out.

Rocks Next Back Rocks are a solid matter made up of minerals. Rocks are found in large quantities in the earth's crust. They are formed by heat or pressure. Next Back

Minerals Minerals are inorganic materials forming naturally in the earth. Minerals are usually categorized by their property. Minerals usually have crystal structure and a hardness by chemicals. Back Next

Is it a rock or a mineral? Clues: Forms from layers of sand-sized grains in the earth’s crust

It is a rock called Sandstone and is made up of minerals such as Quartz.

Is it a rock or a mineral? Clues: Forms crystals although not very large ones

It is a mineral called Talc It is a mineral called Talc. Talc has a soapy feel and can be scratched by a fingernail.Used in powder and many other things.

Is it a rock or a mineral? Clues: Forms from lava from a volcano

A rock called Obsidian formed from cooled lava and forms into glass.

Rocks are formed in 3 different ways.

Click each picture to learn about the three kinds of rocks. metamorphic sedimentary igneous

Sedimentary Rocks Back For thousands, even millions of years, little pieces of our earth have been eroded--broken down and worn away by wind and water. These little bits of our earth are washed downstream where they settle to the bottom of the rivers, lakes, and oceans. Layer after layer of eroded earth is deposited on top of each. These layers are pressed down more and more through time, until the bottom layers slowly turn into rock. Back

Metamorphic Rocks Back Metamorphic rocks are rocks that have "morphed" into another kind of rock. These rocks were once igneous or sedimentary rocks. How do sedimentary and igneous rocks change? The rocks are under tons and tons of pressure, which fosters heat build up, and this causes them to change. If you examine metamorphic rock samples closely, you'll discover how flattened some of the grains in the rock are. Back

Igneous Rocks Back Next Igneous rocks are called fire rocks and are formed either underground or above ground. Underground, they are formed when the melted rock, called magma, deep within the earth becomes trapped in small pockets. As these pockets of magma cool slowly underground, the magma becomes igneous rocks. Igneous rocks are also formed when volcanoes erupt, causing the magma to rise above the earth's surface. When magma appears above the earth, it is called lava. Igneous rocks are formed as the lava cools above ground. Back Next

What type of rock is it? Clues: Find lots of these rocks in Hawaii near volcanoes.

An igneous rock called Pumice formed from cooled lava An igneous rock called Pumice formed from cooled lava. It is so light it will actually float. It is used in soaps.

What type of rock is it? Clues: This rock may have once been sandstone or granite.

A metamorphic rock called Gneiss (pronounced “nice”) A metamorphic rock called Gneiss (pronounced “nice”). Usually made up of many layers of other rocks and minerals.Used for paving & building.

What type of rock is it? Clues: Could be found at the bottom of the ocean where it was formed.

A sedimentary rock called Limestone formed from a mineral called calcite at the bottom of oceans or rivers. Can be used for concrete.

Now, let’s test your skills as a Rock Hound. Click the picture below to go to a web page that allows you to create a word search using terms you have learned from studying about rocks and minerals.