Chapter 1 “Minerals of the Earth” chapter test study guide
1.
What is the difference between fracture and cleavage?
fracture is when minerals break unevenly along curved or irregular surfaces
cleavage is when minerals break along smooth, flat surfaces
2. What 2 things can you do to reduce the negative effects of mining for minerals?
mine reclamation, and the recycling of minerals already mined
3. What are the hardest and softest minerals on Mohs hardness scale?
talc is the softest and diamond is the hardest
4. What is the definition of ore?
a mineral deposit large enough and pure enough that it is profitable to mine
5. What are the 4 characteristics of being a mineral?
naturally occurring, nonliving/inorganic, crystalline structure, and is a solid
6. What are gemstones and why are they valuable?
Gemstones are nonmetallic minerals that are valued for their rarity and beauty
7. What is a crystalline structure?
a repeating pattern of atoms, ion, or molecules in a mineral
8. What are the different types of surface mines?
strip mines, quarries, open pits
9. What are 2 major groups of minerals and what is the difference between them?
silicate minerals – they contain silicon and oxygen
non-silicate minerals – they do not contain silicon and oxygen
10. What 3 things can change the color of a mineral?
exposure to air, water and impurities
11. What is a minerals’ streak?
the powdered form of a mineral which comes from rubbing that mineral on a streak plate
12. What is luster and what are the 3 types?
Luster is the way in which a mineral reflects light.
The three luster’s are: metallic, nonmetallic, and submetallic
13. How many naturally occurring elements are there?
92
14. What is density?
the ratio of the mass of a substance to the volume of the substance
15. What is a streak plate?
It is a piece of unglazed porcelain which is used to rub minerals on to get their powdered form called a streak
16. What machine is used to detect radioactivity?
Geiger counter
17. What are the four items typically used in a laboratory setting to help determine hardness, using Mohs scale?
fingernail – 2.5
copper penny – 3
steel nail – 5.5
glass -- 6
18. If you were to draw cleavage and fracture examples, how might you do so?
Cleavage:
Fracture:
19. When referring to minerals, what does the term hardness mean?
the minerals resistance to being scratched
20. What numbers are used on Mohs hardness scale? Make sure to indicate which number is softest and hardest.
1 to 10. 1 is the softest (talc) and 10 is the hardest (diamond)
21. What is a native element?
a mineral made of only one element
22. What determines how a mineral breaks?
its arrangement of atoms
23. There are 6 special properties used to identify minerals. List what they are and how they are used to identify
minerals.
1.
2.
3.
4.
5.
6.
Fluorescene – radioactive elements wil glow when exposed to UV light
Magnetism – both magnetite and pyrrhotite are natural magnets
Chemical Reaction – calcite will fizz when exposed to weak acids
Taste – halite tastes salty
Optical properties – a thin, clear layer of calcite will make a double image
Radioactivity – minerals with radium or uranium will be detected by a Geiger counter