1. Building blocks of rocks and our Earth. Chapter 29 section 3
Minerals
Building blocks of rocks and our Earth.
Chapter 29 section 3

2. What is A Mineral?
Mineral - a solid, naturally-occurring, inorganic element or compound with defined chemical composition. They are also crystalline in structure. Based on regular arrangement of atoms or ions within it.

3. Rock forming minerals very common on Earth’s surface
The 20 most common make up 95% of Earth’s crust
Quartz, and orthoclase feldspar are the most common
Silicate minerals – minerals containing atoms of silicon (Si) and oxygen (O).
Nonsilicate – minerals that do not contain Si. There are 6 groups.

4. Crystalline Structure
Crystal – natural solid with definite internal pattern.
Large crystals show internal structure
If crystal forms in UNRESTRICTED environment a single large crystal WILL develop.

5. Identifying Minerals
Characteristics of Minerals – minerals are identified by their properties.
Color- the color of it. Color is unreliable
Luster- the way light is reflected from fresh surface of the mineral
Metallic: looks like polished metal.
Nonmetallic: glasslike, waxy, pearly, brilliant (diamond), dull or earthy, and many more.

6. Identifying Minerals
Streak- color obtained when mineral is rubbed across the surface of an unglazed porcelain tile.
Streak is more important than color mineral true color.
Cleavage - tendency of mineral to split on flat surfaces.
Fracture – tendency of mineral to break unevenly

7. Identifying Minerals Hardness - Resistance of a mineral to scratching
Moh’s Scale of Mineral Hardness.
19th century German mineralogist, Friedrich Moh.
Know the chart on page 578.

8. Identifying Minerals . Common materials to estimate hardness
fingernail-hardness about 2.5
copper penny-hardness 3 to 3.5
steel nail-hardness 5 to 5.6
window glass-hardness 5.5 to 6

9. Rocks

10. Types of Rocks
Metamorphic Rocks
Igneous Rocks
Sedimentary Rocks

11. Types of Igneous Rocks
Intrusive: Formed underground by trapped, cooled magma, large mineral crystals
Extrusive: Formed above ground when volcanoes erupt and magma cools, smaller mineral crystals.

12. Examples of Igneous Rocks
Intrusive Igneous
Extrusive Igneous
Scoria
Granite
Obsidian
Diorite

13. Sedimentary Rocks How They are Made
Wind and water break down the earth
Bits of earth settle in lakes and rivers
Layers are formed and build up
Pressure and time turn the layers to rock

14. Sedimentary Rock Classification
Clastic – composed of fragments (clasts) of pre-existing rock transported some distance from their points of origin
Chemical – form when standing/trickling water evaporates, leaving dissolved minerals behind.
Organic – an accumulation of sedimentary debris caused by organic processes. Plants and animals.

15. Types of Sedimentary Rocks
Sandstone Clastic
Limestone Organic
Gypsum Chemical
Conglomerate Clastic
Shale Clastic

16. Metamorphic Rocks Rocks that have changed
They were once igneous or sedimentary
Pressure and heat changed the rocks
2 types: Regional and Contact
Contact occurs near magma chambers
Regional occurs where continents collide

17. Types of Metamorphic Rocks
Marble
Gneiss

18. Rocks Have Been Used For Many Years and For Many Things

34. Rocks