Rocks and Minerals

1. Rocks and Minerals

2. “Learning Target”…….. • “I Can…..” Identify the differences between a mineral and a rock.

3. What is a mineral? • A mineral …… • Is a Inorganic solid formed in nature • (Inorganic -- not living or ever been living. • It is not formed by plants or animals) • Has a characteristic“fixed”chemical • composition • Has distinctive physical properties • Has a Crystalline structure (-- an orderly • arrangement of atoms)

4. Crystals • Minerals with some solid, geometric shape to them are called crystals. They are produced by a repeating pattern of atoms that is present through-out the mineral. • Crystals can be made from different elements: • (ex: diamonds –are made from carbon) • (salt—is made from the elements sodium and • and chlorine.

5. Crystals cont’d • A crystal’s shape is determined by the arrangement of the atoms within the crystal. • A crystal’s color is determined by the elements that are mixed in. • Crystals are not just what we think of as jewelry. You actually eat many different types of crystals( such as salt, sugar, baking soda)

6. Minerals are more common than you think…. Currently, about 4,000 minerals have been identified, and 50 to 100 new minerals are discovered each year!! We use them in our everyday households such as metal pots and pans, salt shakers, dishware, and even glassware!!!

7. How do minerals form? • They form in several ways: • 1. From melted rock inside the Earth called magma • As it cools the atoms combine in orderly patterns to form minerals • 2. From magma that reaches Earth’s surface, called lava • As it cools the atoms combine in orderly patterns to form minerals • 3. Evaporation of dissolved minerals • From precipitation *water can hold dissolved minerals.

8. Properties of Minerals include: • Color Luster • Streak Hardness • Cleavage & Fracture • Density • Specific Gravity • Special Properties

9. Color: Not Mineral Specific It’s the LEAST reliable way to classify a mineral!!

10. Metallic Non-metallic Luster: (shininess) It’s describes how minerals reflect light

11. Streak: Is the mineral in it’s powdered form of a mineral NOTE: The color of a mineral’s streak is not always the same as the color of the mineral sample.

12. Cleavage & Fracture Describes how different types of minerals break in different ways. Cleavageis the tendency of some minerals to break along smooth, flat surfaces. Mica Biotite Mica • Fractureis the tendency of some • minerals to break unevenly along • curved or irregular surfaces Calcite

13. Hardness: A mineral’s resistance to being scratched. This is tested using the Mohs’ Scale of hardness (pg. 272)

14. The Mohs’ scale was founded by an Austrian geologist: Fredrich Mohs.

15. Ooohhh!! Diamonds! • Diamonds are the hardest known mineral (10 on Mohs’ Hardness Scale) • They are formed very deep in the Earth and at great pressure • It takes 250 tons of Earth to obtain a 1.00 Ct Diamond! • It takes 1405 degrees of heat to burn a Diamond! • Only Diamonds can Scratch or Polish another Diamond! • Diamonds come in wonderful fancy colors like, Pink, Blue, Green, Champagne, Black, Chocolate, Yellow, Red, Gray, and even Purples! (such as the famous HOPE diamond, which is blue!!)

16. Did You Know? • The largest diamond in the world is the Cullinan diamond weighing 3,106 carats! It was cut into 105 separate diamonds.

17. Trivia Question: If Diamonds are the hardest mineral, what is the second hardest mineral? Corundum!!!! Which is the mineral name for ruby and sapphire.

18. Density and Specific Gravity • Densityis the measure of how much matter is in a given amount of space. • Density is a ratio of an object’s mass to its volume. (D= m/v) • Different minerals have different densities. • A mineral’s Specific Gravity compares the weight of a mineral with the weight of an equal volume of water.

19. Special Properties • Some properties are particular to only a few types of minerals. - The properties shown on the next slidecan help you quickly identify some minerals.

20. Special Properties

21. Gems • are rare minerals that can be cutand polished, giving them a beautiful appearance • Ideal for jewelry • Are rare and are therefore valuable • Must be made under tremendous amounts of heat and pressure, deep in the Earth’s mantle • It takes a certain kind of volcanic eruption to bring diamonds close to the surface

22. Ores • A mineral is called an ore if it contains enough of a useful substance that it can be sold for a profit • Metals that people use, such as: • Iron used to make steel comes from hematite • Lead for batteries comes from galena • Magnesium in vitamins comes from dolamite • In order to obtain these ores, they must be mined

23. “Learning Target”…….. • “I Can…..” Use a table of physical properties to classify minerals.

24. What is a Mineral?

25. What is a mineral? A mineral is a naturally formed, inorganicsolid, with a fixedchemical composition , that has a definite crystalline structure.

26. What is a mineral? • Solid • Cannot be a liquid or a gas • Naturally Occurring • Found in nature, not man-made • Inorganic • Is not living nor has ever been living • Fixed chemical composition • Has a definite chemical formula, most are formed from two or more elements, but some minerals consist of one element ex. Au • Crystalline structure • A definite structure in which atoms are arranged in a geometric pattern

27. Questions to askyourself when determining if an item is a mineral or not: The next few slides show an assortment of items. On your ½ sheet, fill out the T-chart and categorize the items as either: Minerals (M)or Non-Minerals (NM) • Is it non-living material? • Is it a solid? • Is it formed in nature? • Does it have a crystalline structure?

29. Gold

30. Fossil

31. Topaz

32. Bones

33. Granite

34. Quartz

35. Pearls

36. Talc

37. Icebergs

38. Diamond

39. Coal

40. Rock Salt

41. And the answers are… • Minerals • Gold • Topaz • Quartz • Talc • Iceberg* • Diamonds • Non-Minerals • Wood - once living • Fossils – once living • Bone - living material • Granite - intrusive igneous rock • Pearls – made by oysters • Coal - Sedimentary rock • Rock Salt – Sedimentary rock *FYI: According to the MA (International Mineral Association) ice is listed as a mineral!

42. Quick Check….. • Can you name all eight physical properties of minerals? • Color • Luster • Streak • Hardness • Cleavage & Fracture • Density • Specific Gravity • Special Properties

43. Update your ISN… p. 36: “Practice: Identifying Minerals” Objective: I can use a chart to identify minerals.

44. “Learning Target”…….. • “I Can…..” Use a table of physical properties to classify minerals.

45. Assignment……… • Use your table # to complete the “Minerals Identification” lab. • When you finish, glue to p. 39

46. Hint: The Minerals can only be one of the following: Fluorite Halite Gypsum Calcite Quartz Feldspar Galena Mica Talc

47. Bellwork 9/18/14 Look at the different mineral samples provided. Then, list GOOD, reliable properties that could be used to distinguish between the two minerals. What property would be the least reliable way to identify them and why? Apply what you have learned about minerals!!  Sample 1 Sample 2 47

48. “Learning Target”…….. ISN p.40: • Objective: • I can distinguish between the three different types of rocks.

49. ROCKS and the Rock Cycle!!!

50. So What Exactly is a Rock?? • A rock is a naturally occurring solid mixture of one or more minerals and “organic”matter. • Rocks go through a “cycle”, meaning they are always changing into different forms. They are continually being “recycled” through a process called the “Rock Cycle”. • Can you think of another “cycle” that you have learned about in Science?