1. Chapter 9: Rocks and Minerals
Lesson 1: What are rocks and minerals?

2. What are rocks and minerals?
Mineral: a natural forming, nonliving solid with a definite chemical structure
Examples: gold, quartz, diamond, emerald, copper, ruby, (gem stones)
Rock: a solid, natural material made up of one or more minerals
Crystals: makes up minerals and form when minerals are made in nature

3. What are rocks and minerals?
Mohs Hardness Scale: used to tell the difference in hardness of minerals
Based on how hard it is to scratch the surface
Examples: talc is a 1 (very soft) and diamond is a 10 (very hard)
Mineral Properties: hardness, cleavage pattern, crystal shape, luster, scratch test

4. What are rocks and minerals?
Rock Cycle: a pattern of change in rocks when they break down and the minerals in the rocks are recycled
This is where the 3 main types of rocks are formed:
Sedimentary
Igneous
Metamorphic

5. Igneous Rocks
SedimentaryRocks
Metamorphic Rocks

6. What are rocks and minerals?
Sedimentary Rock: made from pieces of rocks and minerals
Forms in layers (oldest at the bottom)
“history book”—where you find fossils and helps to date them
Example: limestone

8. What are rocks and minerals?
Igneous Rock: forms when magma or lava cools and hardens
This can happen underground (magma) or above ground (lava)
Ignis
Latin for FIRE
Cool quickly=fine-grained rock
Cool slowly=coarse-grained rock

10. What are rocks and minerals?
Metamorphic Rock: forms when heat, pressure, or chemical reaction change one type of rock into another type
Made from Sedimentary rock or igneous rock

12. What are rocks and minerals?
Relative Dating: using evidence found in sedimentary rock scientists can learn the relative age of each layer and the materials found in it
Example: layers of the Grand Canyon

13. What are rocks and minerals?
Fossils: formed when an organism is buried (e.g. soft mud) and then preserved
Minerals will fill into the organism, hardening them (preserving them)
Usually only the hard parts from the organism (bones, shells, wood, etc) will survive
Example: petrified wood, trilobites and dinosaur footprints
~5 inches

14. “A trail of giant footprints left behind by a massive 30-ton dinosaur has been discovered in a quarry in Germany” in August of 2015.
“Scientists say the footprints, which each measure four feet across and are 17 inches deep, were made by a sauropod, or long-necked dinosaur, 135 to 145 million years ago.”—Quote and photo credit:

15. Arctinurus boltoni
Trilobites
Silurian Time Period: (~ MYA)
Size: 125 mm (~5 in)
Fossil Site: Rochester Shale Formation, Middleport, New York

16. Chapter 9, Lesson 1: What are rocks and minerals?
END of Lesson 1 Questions!
Q: What is the difference between cleavage and fracture?
A: Cleavage: the ability to split along flat planes
Fracture: breaking into uneven parts
Q: What role does pressure have in the rock cycle?
A: Pressure is involved in the formation of both sedimentary rock and metamorphic rock.
Q: A scientist finds a layer of rock in which there are fossilized marine organisms. Although the rock layer was found in the middle of Ohio, what conclusion can be reached about the history of the area?
A: At one time, the area was covered by salt water.