Minerals Properties Lab Key

Luster
Mineral name Chemical formula Describe the luster
1. galena PbS  
2. chalcedony SiO2  
3. limonite Fe2O3 · H2O  
4. Which two of these have a nonmetallic luster?
Color
Mineral name Chemical formula Describe the color
5. fluorite CaF2  
6. pyrrhotite FeS  
7. amphibole CaNa(Mg or Fe)4(Al or Fe or Ti)3Si6O22(O or OH)2
8. Why isn't color a reliable identifier of minerals?

Streak
Mineral name Chemical formula Describe the streak color
9. chalcopyrite CuFeS2  
10. galena PbS  
11. specular hematite Fe2O3  
12. What is surprising about the color of one of these streaks?

Hardness
Mineral name Chemical formula Range of Mohs Hardness numbers
13. Al2O3  
14. Mg3Si4O10(OH)2 Talc  
15. KAlSi3O8 Orthoclase

Heft
Mineral name Chemical formula Heavier or lighter?
16. gypsum Mg3Si4O10(OH)2  
17. magnetite Fe3O4  
18. How would looking at the chemical formula help you answer heavier or lighter?

Cleavage / Fracture
Mineral name Chemical formula Does the mineral exhibit cleavage or fracture?
19. muscovite KAl3Si3O10(OH)2  
20. quartz SiO2  
21. calcite CaCO3  

Special Properties
Mineral name Chemical formula Describe a special property
22. magnetite FexOy  
23. sulfur S  
24. Why are there variables (x and y) in the chemical formula for magnetite?
25. What other minerals in this lab might have the same special property as magnetite? Why do you think this?  

Crystal Form
Mineral name Chemical formula Does the mineral have regular (repeating pattern) or irregular crystalline shape?
26. halite NaCl  
27. malachite Cu2CO3(OH)2