Minerals Flashcards
How many known mineral types are there?
~4500
How many minerals are common enough to be considered rock-formers?
40
How many minerals are common all over the earth?
12
How many minerals make up 90% of the earth’s crustal weight?
10
Most minerals are a combination of what?
Oxygen (O) and Silicon (Si)
What are the most abundant elements in the Lithosphere?
Oxygen (O), Silicon (Si), and Aluminum (Al)
Essential Mineral
Must be present to make a specific rock.
Accessory Mineral
Doesn’t matter whether or not it’s in a rock and doesn’t change the type of rock.
Mineral
must be…
- Inorganic (non-living)
- Natural
- Solid
- Contain an orderly structure of chemical composition
What are the 2 mineral chemical classes?
Silicates and Carbonates
What is the most abundant mineral group and makes up 50% of the earth’s crust?
Feldspar
What is the second most common mineral in the continental crust?
Quartz
What is the basic building block of geology?
Silica Tetrahedra
What are the 2 silicate subgroups?
Ferromagnesian and Non-Ferromagnesian
Ferromagnesian
- Contains Iron (Fe) and Magnesium (Mg)
- Dark in color
- Specific gravity between 3.2 and 3.6
MAFIC
Non-Ferromagnesian
- DOES NOT contain Iron (Fe) and Magnesium (Mg)
- Light in color
- Average specific gravity of 2.7
FELSIC
Mafic
Ferromagnesian (dark colored)
Felsic
Non-Ferromagnesian (light colored)
Ferromagnesian Silicates (basic rock-formers)
- Olivine
- Augite (Pyroxene)
- Hornblende (Amphibole)
- Biotite (Mica)
- Garnet (dark)
Olivine
- Vitreous luster
- Olive-Green color
- Scratches glass
- No cleavage
- Granular masses
Augite
- Vitreous luster
- Dark Green or Black color
- Scratches glass
- Shows cleavage
- Stubby crystal
Hornblende
- Vitreous luster
- Dark Green or Black color
- Scratches glass
- Shows cleavage
- Hexagonal and elongated
Biotite
- Vitreous/Pearly luster
- Dark Green, Brown, or Black color
- Does not scratch glass
- Shows cleavage
- Forms thin elastic sheets
Garnet
- Vitreous/Resinous luster
- Dark Red or Reddish Brown color
- Scratches glass
- No cleavage
- Brittle
*Also comes in Felsic light colors
Non-Ferromagnesian Silicates (basic rock-formers)
- Feldspar
- Muscovite (Mica)
- Quartz
- Talc
- Kaolinite (Kaolin)
- Garnet (light)
Feldspar
- Vitreous luster
- White, Cream, Pink, Gray, or Reddish Brown color
- Scratches glass
- Shows cleavage
- Comes in Plagioclase and Orthoclase (Potassium K Feldspar)