What term is used to describe the shape of a mineral that has three directions of cleavage that intersect at 90-degree angels?

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What term is used to describe the shape of a mineral that has three directions of cleavage that intersect at 90-degree angels?

The Study of Minerals
*Use upload for pictures
1. Name the physical property (hardness color streak etc.) described by each of the following statements.
DESCRIPTION: PHYSICAL PROPERTY:
Breaks along smooth planes: ___________________________________
Scratches glass: _______________________________________
Shines like metal: __________________________________
Scratching produces a red powder: _____________________________
Looks like broken glass: ______________________________
2. What term is used to describe the shape of a mineral that has three directions of cleavage that intersect at 90-degree angels? _______________________________
3. Describe the cleavage fo the minerals listed below. include the number of directions and degrees of cleavage angles (if appropriate).
MINERAL: CLEAVAGE:
Muscovite: _____________________
Calcite: _______________________
Halite: ______________________
Feldspar: _____________________
4. What physical feature most distinguishes biotite mica from muscovite mica? __________________________
5. Name a mineral that exhibits the physical properties listed below. (use the Photos in the upload if needed)
PROPERTY: MINERAL:
One direction of cleavage: ________________________
Striations: ________________________
Multiple Colors: __________________
Cubic cleavage: ______________________
Nonmetallic vitreous luster: ______________________
Fracture: _____________________
Metallic luster: _____________________
6. Figure 1.32 illustrates the common crystal form of the mineral fluorite and the characteristic shape of a cleaved sample of fluorite. Identify each specimen (A or B) next to its appropriate description below.
Cystal form of fluorite: ____________
Cleavage specimen of fluorite: ___________
7. Refer to the photo in Figure 1.33 to complete the following.
a. Describe the crystal form (habit) of this specimen.
______________________________________________________________________________
b. What term is applied to the lines on this sample?
______________________________________________________________________________
c. Based on what you can determine from this photo use the mineral identification key (see figure 1.24) to
identify this mineral.
______________________________________________________________________________
8. A photo of agate a variety of quartz composed of microscopically small crystals is provided in Figure 1.34. Based on this image describe the habit of this sample.
_______________________________________________________________________________
_______________________________________________________________________________
9. If a mineral can be scratched by a penny but not by a fuman fingernail what is its hardness on the Mohs scale?
____________________________
10. What term is used to describe the tenacity of muscovite?
_________________________________________
11. Use the mineral identification key (see Figure 1.24) to identify a mineral that is nonmetallic dark colored harder than glass lacks cleavage and is green in color. _________________________________
12. For each mineral listed below list at least one diagnostic property.
MINERAL NAME: DIAGNOSTIC PROPERTY
Halite: ______________________________________
Galena: ______________________________________
Magnetite: _____________________________________
Muscovite: _____________________________________
Hematite: ______________________________________
Fluorite: _______________________________________
Talc: _________________________________________
Graphite: ______________________________________
Calcite: _______________________________________
13. List the two most common rock-forming mineral groups.
_____________________________________
_____________________________________
14. Providean economic use for each mineral listed below.
Galena: _______________________
Hematite: _____________________
Graphite: ______________________
Sphalerite: _____________________
Gypsum: ______________________
Calcite: _______________________