3-Rocks and Minerals are clues for understanding what happened on Earth in the, the and the.

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1 Geology is the study of the earth. Many geologists study rocks and minerals, as rocks and minerals are some of the best clues to understanding: The Earth s past, present, and future. Everything from land movement billions of years ago, To what is at the centre of the Earth, To where earthquakes are likely to happen And when volcanoes are likely to erupt. Complete the questions. 1-What is Geology? 2-What things do many Geologists study? 3-Rocks and Minerals are clues for understanding what happened on Earth in the, the and the. 4-What things can rocks and minerals tell us? Minerals are not just buried deep in rocks; they can be found around your house! In the kitchen you might find table salt (mineral: halite), aluminum foil (mineral: aluminum), and copper pots (mineral: copper). In your pencil case, you might find pencil lead made of mineral called graphite.

2 Rocks A rock is combination of minerals. Each type of rock is made up of the same minerals, but their concentration may vary. For example, granite is composed primarily of quartz, feldspar and mica, but their proportion may vary from one type of granite to the next. These differences are what create the different varieties within groups of rock, such as pink granite and white granite. Minerals Minerals are solids with specific chemical compositions and unique properties (e.g., iron, gold, silver, copper, platinum, bronze, sulfur, diamonds, graphite, pyrite, magnetite, halite, calcite, gypsum, mica, quartz, feldspar, etc.). Minerals are what rocks are made of. Rocks classification Rocks are classified according to how they are formed. There are 3 types. They can be igneous, sedimentary or metamorphic. Igneous rocks are hard rocks possessing variably colored crystals. There are two types of igneous rocks: Intrusive igneous rocks, which are formed from magma (molten rock) that slowly cools within the Earth s crust (Ex. Granite) Extrusive igneous rocks, which are formed from magma that cools rapidly as it leaves the Earth s crust (porous volcanic rocks Ex. Pumice, Obsidian, Basalt). Magma is called lava when outside of the earth. Sedimentary rocks are formed by the accumulation of different sized sediments. This usually occurs at the bottom of bodies of water. Most of these rocks are made up of many layers, or strata, that are often invisible to the naked eye. They sometimes also contain fossils. (Ex. Sandstone from sand, Limestone from shells, Shale from mud, Coal from plants and animals) Metamorphic rocks are igneous or sedimentary rocks that have been changed or transformed by intense pressure or extreme heat. Their appearance varies greatly, ranging from glass-like to a laminate-like texture. (Ex. Marble was made from limestone. Gneiss was once granite.)

3 Complete with the correct word. colour inorganic rock crystal minerals 1-A solid material made up of one or more minerals is a. 2-There are 3000 different on earth and they form naturally and are made up of one substance. It is the same inside and out. 3- Minerals are, which means they are not, and never were, alive. 4-Minerals can be different in their, shape and hardness, but they are capable of forming a. lava magma 5-Melted rock above the earth's surface is called 6-Melted rock beneath the earth's surface called large small 7-When magma cools slowly, minerals with crystals are formed. 8-When magma cools quickly, minerals with crystals are formed. igneous sedimentary metamorphic three 9-There are types of rocks. 10-Rocks that form from layers of sediments are called rocks. These layers are called strata. 11-Rocks that form when melted rock cools and hardens (made from lava or magma) are called rocks. They are also known as fire rocks. 12-Rocks that form under pressure and heat and have gone through a major change or transformation within the earth are called rocks.

4 ROCK TYPES Complete with the correct word, Metamorphic Igneous Sedimentary Granite: Cooled slowly underground Basalt: Cooled quickly above the surface of the earth Sandstone: Compressed sand Shale: Formed from mud Chalk: Formed from compressed shells and sea animals Marble: Was made from Limestone Gneiss: Was once Granite pumice obsidian coal limestone 1-This sedimentary rock is made out of the shells and pressure from other shells, and from the water, and from sand being washed over the shells, squishing them all together into rock. It is. 2-This sedimentary rock is black and was made by decaying plants that lived long ago. It is also used for starting a fire on a BBQ. It is. 3-This igneous rock was cooled very quickly and does not have any crystals. It is very light and special because it can float. It is. 4-This igneous rock is glassy and black. It is. Rocks of different sizes have different names. Put the rocks on a scale from smallest to largest. boulder clay mountain pebble sand silt stone 1_clay 2_silt smallest largest

5 Read the text below and answer the questions. Rocks are the sand and pebbles on the beach, the mountains we climb, and the ground beneath us. But what are they made of? Rocks are all made of one or more minerals. Different rocks have different combinations and amount of minerals. Some minerals that can be found in rocks are mica, quartz, calcite and orthoclase. A-List four examples of rocks B-What are rocks made of? C-Write the mineral content of these rocks arkose granite marble -o -o -c -q -q -m Read the text below about a fossil and answer the questions. About eight million years ago, a large marine reptile died and was buried in the muddy bottom of the shallow sea where it once swam. Years passed and the bones mineralized underneath layer upon layer of sand and mud, which became a sedimentary rock that covered the bones. A fossil was formed. 1-What is a fossil? a)layers of sand and mud b) the remains of a plant or an animal that lived long ago c) anything that is old 2-Tell whether each of these is a fossil or a trace fossil. a-tooth b-footprint c-bone d-fern impression e-ammonite impression Interesting Fact- While the remains of any plant or animal can become a fossil, sometimes an imprint, such as a footprint, is found. This is called a trace fossil.

6 How are Minerals Identified? Minerals have certain properties, or characteristics, that help to identify them. Minerals can be identified by their odor, colour, luster, transparency, streak, cleavage, hardness. Colour is not always a good clue to the identity of a mineral. Many minerals are found in several colors and many minerals have extra chemicals in them that give them an unexpected color. Also, weathering may change the color of the mineral. For example quartz comes in various colors: rose, milky, clear Luster is the way a mineral reflects light. Minerals can be described as metallic, pearly, glassy, silky, greasy, brilliant, or dull. For example, diamonds are brilliant. Talc has a greasy luster, quartz has a glassy luster, and gypsum has a pearly luster. Pyrite or fool's gold, as it is sometimes called, has a metallic luster. Streak test- This is the color of the streak made by rubbing a mineral across a hard, rough surface like a bathroom tile. An example is pyrite which is a brassy, yellow color. However, it makes a greenish, black streak when rubbed across a rough surface. Cleavage and Fracture is when certain minerals break in a definite way. For example, galena cleaves into little cubes. Mica cleaves into thin sheets. Calcite cleaves into slanting bricks. Feldspar breaks into little steps. Quartz cleaves into irregular chunks. Hardness is measured by seeing how easy it is to scratch a mineral For example, talc, the softest mineral known, can be scratched witha fingernail. Diamond, the hardest mineral, can scratch all the other minerals but cannot be scratched by them. A German mineralogist, Friedrich Mohs, developed a standard scale of hardness in His scale is so easy to use that it is still in use today. Magnetic such as magnetite, which is a natural magnet, have magnetic properties. Transparency- The ability to transmit light. Many rocks are opaque(can not see through it) when in a chunk, are translucent (can see through it) when cut into very thin slices. Gems stones are often valued on how clear, or transparent they are. Ex. Rubies, sapphires, emeralds, diamonds

7 PROPERTIES OF MINERALS Write the properties that can use to identify minerals and the words we use to describe them. Luster Colour Streak Hardness Transparency 1- How well light can pass through a mineral: Ex. Opaque, translucent, and transparent 2- The way the light reflects off a mineral s surface: Ex. Metallic, glassy, waxy, dull 3- A mineral s colour: Ex. White, black, grey, brown, red, green, blue, purple, orange, gold, silver, bronze 4- How difficult it is to scratch a mineral: Ex.hard and soft 5- The colour of a mineral s powder: Ex. White, black, grey, brown, red, green, blue, purple, orange, gold, silver, bronze What properties of minerals do the tests reveal? TEST #1 Scratching a mineral with another mineral. Property revealed: 1- TEST #2 Rubbing a mineral on a rough surface to see if it leaves a streak Property revealed: 2- TEST #3 Observing how light interacts with a mineral Property revealed: 3- Match the mineral sample with their descriptions an circle the correct word. Gold Turquoise Quartz 1- green, leaves a bluish streak, (metallic/waxy), (opaque/transparent) 2- yellow, leaves a yellow streak, (metallic/glassy), (opaque/translucent) 3- colourless, leaves a white streak, (glassy/dull), (opaque/translucent)

8 Complete the Mohs scale with the following information. The Mohs Hardness Scale list certain minerals from 1 to 10, with 1 being the softest an 10 being the hardest. A mineral has the ability to scratch another mineral that is softer, but not one that is harder. Every mineral has then been given a hardness number based on the ability to scratch and be scratched. Talc is the softest mineral. Corundum is the second hardest. Calcite is harder than talc and gypsum only. Diamond is harder than corundum. Orthoclase can scratch apatite but not quartz. There are 4 minerals on the scale that apatite can scratch. Flourite is harder than calcite and softer than apatite. Quartz can be scratched by topaz. MOHS SCALE OF HARDNESS SOFTEST HARDEST 2.5 finger nail 3 penny 5 pen knife blade 6 glass 7.5 metal file Look at the Mohs Scale and fill in the blanks or circle the best answer. 1- Seven minerals in the chart are softer than 2- The softest mineral is. 3- Corundum is softer than. 4- Flourite is than calcite. 5- Quartz is than topaz. 6- Gypsum is harder than. 7- will scratch gypsum but not fluorite. 8- will scratch apatite but not quartz. 9- Halite can scratch gypsum but not calcite. The scale of hardness of halite is in between and. 10- On this scale, each mineral can scratch the ones ( below / above) it, but none can scratch a mineral ( below / above) it.

9 Look at the Rock Cycle Diagram. Fill in the blanks and answer the questions. THE ROCK CYCLE 1- Igneous and rocks can become rocks under intense heat and pressure. 2- When and metamorphic rocks break down into small pieces and are carried away in a process called, they can become rocks. 3- Metamorphic and rocks can become rocks if they melt into magma. 4- How do metamorphic rocks become igneous rocks? 5- How do sedimentary rocks become metamorphic rocks? 6- How do igneous rocks become sedimentary rocks? 7- What happens to sedimentary rocks when they are exposed to heat and pressure?

10 THE ROCK CYCLE- Read the text. The complete the chart with the underlined words. The rock cycle shows us that heat and pressure can turn both sedimentary and igneous rocks into metamorphic rocks. Here are some examples. Sandstone and limestone, common sedimentary rocks, turn into quartzite and marble respectively. Shale, a sedimentary rock made of silt, becomes slate. Granite, a common igneous, becomes gneiss. Rock Sedimentary Rock HEAT AND Igneous Rock PRESSURE Fill in the blanks with the given word. erosion sand mountains sedimentary cycle moving water Erosion--- Pebbles, 1-, clay and silt come from larger rocks, which can come from landforms like 2-. Glaciers, landslides, 3-, and plant roots break off or break down rocks causing 4-. All three types of rocks can be eroded into small pieces and eventually settle into the sea to become 5- rocks. Erosion destroys rocks, and is an important part of the rock 6-.