Do you want to be a rock star?

Let’s work on it.

Minerals – naturally occurring (found in nature, not man made) Inorganic (not living) Geometric shaped Crystalline structure Specific chemical composition

Minerals - what rocks are made of, the “building blocks” of rocks

Properties (characteristics)1. Hardness – measured on the Moh’s scale, can it scratch or be

scratched by another rock

2. Luster – the way a mineral reflects light (metallic, non metallic (not shiny), or brilliant)

3. Streak – the color of the powder when you rub the mineral on porcelain, for example, minerals may leave a white powder even though they look brown or gray

4. Texture – how a rock feels

5. Density – the specific weight6. How a mineral breaks Cleavage or fracture

A. Cleavage – if a mineral splits easily and evenly we say it has cleavageLook at the smooth edges.

B. Fracture – if a mineral breaks and has jagged edges we say it has fractureNotice how jagged and uneven the breaks are.

Rocks are classified (put in groups) according to how they were

formed. There are 3 classifications.

What makes each type of rock different? Let’s find out.1. Igneous - made from melted rock like magma or lava that

has cooled

There are 2 kinds of igneous rock. It depends on where the rock cooled. Remember: it melted first

1. Intrusive igneous rocks – form when they cool slowly deep inside the earth Magma is inside the earth.

2. Ex trusive igneous rocks – form when they cool quickly outside the earth from lava Think: exit is a way out.

Examples:

What is the key word to describe how igneous rock formed? Melted

What are they called if they cool slowly inside the earth? _________________________________What are they called if they cool quickly outside of the earth? ______________________________Name 2 kinds of igneous rock. __________________________ & __________________________

2. Metamorphic - made when heat and pressure change existing rocks

Examples

What 2 key words describe metamorphic rock? heat and pressure

Name 2 kinds of metamorphic rock? ______________________ & ______________________

3. Sedimentary - made from layers of sediment (particles of weathered rock) pressed together (pressure but not heat), may contain fossils

You might see the words pressed, pressure, compression, or compaction.

Animals, their bones, or plants may get deposited with the sediment. These form fossils in the sedimentary rock.

Sediment gets pushed together(compacted or compressed).

It sticks together (cemented)

until it forms sedimentary

Can you see the layers? What caused them? Pressure

Examples

Name 4 kinds of sedimentary rock. ______________, ________________

_____________________ & _________________________Weathering – the breaking down of rocks caused by wind, water, temperature (freezing and thawing), or chemical processes like acid rain that wear away the rock. The result is sediment, clay, sand, and pebbles.

Erosion – the moving of the sediment after the rock has been broken downIt can be carried by wind, water, landslides, floods, or gravity.

Deposition – when the sediment is deposited or put some place new

As more and more sediment gets deposited, the pressure builds. Eventually it forms new rock – sedimentary rock!

Can you see where the rock weathered and then eroded away leaving the thin bridge like rock?

Can you answer these questions? If not, go back and look.

Which kind of rock is formed by heat and pressure?________________Can you name 2 examples of this type of rock?

Which kind of layered rock might have fossils? ____________________Can you name 4 examples of this type of rock?

Which kind of rock is formed from melted lava? ____________________Can you name 2 examples of this type of rock?

What is the term to describe when rock is broken down?______________

What is the term describing the movement of broken down rock? ___________________

What kind of rock might have fossils in it? ____________________

Are you rockin’ this?

Do you always stay the same? No. Rocks change too. You may grow fast, but rocks usually change slowly. One kind of rock can become another kind of rock. This is called the Rock Cycle.

If a metamorphic rock gets heated and melts, it can become igneous rock. If igneous rock weathers and breaks down, it will erode and become sedimentary rock. If sedimentary rock is exposed to heat and pressure, it will become metamorphic rock. If igneous rock is exposed to heat and pressure, it too could become metamorphic rock. Can you explain the rock cycle to someone?Maybe this link to rock music will help. https://www.youtube.com/watch?v=53lMdHzvGCQ

Are you still rockin? Keep going; you’re almost a rock star!

Can you read a dichotomous key? Yes, you can. It is just a flow chart. Take off the last page and let’s look at it together.

The table on the left identifies 4 different minerals. It also tells you about their luster, the color of their streak, and their hardness. Look at Mica. The table says its luster is nonmetallic (not shiny). It has no streak (leaves no color behind when you scratch it on a tile) and its hardness is 2. Look at graphite. What is its luster? What color is its streak? Is its hardness 2 or 4?Which mineral has a streak of brown-gray?See, this isn’t hard.

Now, look at the flow chart. At the top it says mineral. The table told us there were 4 minerals.

Next (follow the arrows), the flow chart show a box for nonmetallic and a box for metallic luster. Nothing follows nonmetallic so we can ignore that box now.

From the metallic box are 2 arrows – one points to steak – none and one points to streak – black. Continue following the arrows to the next set of boxes which say hardness. (I use my finger to follow the arrows.) We are looking at hardness. Again we see 2 boxes. One says hardness – 6 and the other says hardness 2.

Look back at the table. Which minerals have a metallic luster and a black streak? You should see 2.

_________________ and _____________________

You’re doing great.

Now, which one has a hardness of 6?

Do you see the box under hardness – 6? It is marked x. Which mineral would go there?________________________

magnetite

So you see the box under hardness -2? It is marked Y. Which mineral would go there? _____________________________

graphite

Finally, look at the question. It asks which mineral belongs in square xPick the correct answer.

Great job! You can read and answer a question based on a

dichotomous key. You are a

Are you still rockin? Keep going; you’re almost a rock star.

Can you read a dichotomous key? Yes! It’s just like a flow chart.Let’s look at this one