Minerals Flashcards
(37 cards)
What is Granite
makes up the Sierra Nevada Mountains. Commonly used for countertops. Quartz, Hornblende and Orthoclase make up granite.
What is a rock?
Rocks are aggregates of minerals.
Earth and its elements
Minerals are the solid manifestation of these elements and their combinations.
What are native elements?
Some elements occur in their native (pure) state. These minerals consist of a single element. Examples are copper and iron (meteorite)
What is Native carbon?
Native carbon takes one of two forms. One is more valuable than the other. Native carbon: Graphite
Native carbon: Diamond. Increase pressure is what pushes from graphite to diamond.
How is a mineral defined?
-Naturally occurring chemical compound
-Solid
-Crystalline (ordered) internal structure
-inorganic
-distinctive chemical formula
Naturally occurring chemical compounds
Chemical compounds are naturally occurring if formed by natural processes. If the compound can only be formed synthetically in a laboratory, then it is not naturally occurring. Example: Iceberg, naturally occurring. Bag of ice, NOT naturally occurring.
Minerals can only be SOLID
Minerals can only be solids. Liquids and gases need not apply. Solid water (ice) would count. Solid H20.
Crystalline internal structure
Crystalline (ordered) internal structure must be predictable and repeatable.
Organic and Inorganic materials
Examples Inorganic: Quartz geode (SiO2) Diamond (c)
Examples: Organic Sugar crystals. Glucose (C6H12O6) Fructose (C6H12O6) Sucrose (C12H22O11)
Inorganic material made from organisms
You can call those minerals
Examples: Sea shells (CaCO3) Shark Teeth (CaPO4)
Minerals have distinctive chemical compositions that give them distinctive physical properties.
Optical properties: Luster, Color, Streak
Mineral Strength: Hardness, Cleavage, Fracture
The way a mineral reflects light is called luster.
Luster is described as metallic or nonmetallic.
Metallic luster: Galena, Gold.
Non-metallic luster: Quartz, Diamonds.
The color of a mineral is easy to observe, however, its often the least diagnostic property.
The color of a powered mineral is its streak. Metallic minerals leave behind a streak that is often different from the mineral crystal color.
A mineral’s hardness refers to its resistance to scratching measured relative to other minerals.
1-Talc, 2-Gypsum, 3-Calcite, 4-Fluroite, 5-Apatite, 6-Orthoclase, 7-Quartz, 8-Topaz, 9-Corundum, 10-Diamond.
A harder mineral will always scratch a softer mineral: Fingernail (2.5), Copper Penny (3.5), Wire nail (4.5), Glass and knife blade (5.5), Streak plate (6.5). Shark tooth (5), Stainless Steel (5.5), Polish paste (6), Dental drill (9.5)
Cleavage
Cleavage is the tendency of a mineral to break along planes of weak bonding. Planes of cleavage create flat mineral surfaces.
Planes of cleavage = flat sides divided by 2
2 flat slides =1 plane (muscovite)
4 flat sides = 2 planes (orthoclase)
6 flat sides =3 planes (Halite)
8 = flat sides =4 planes (Diamonds)
Minerals that have ZERO cleavage
Minerals that have zero directions of cleavage, meaning no cleavage, have no distinct shape. Olivine is a good example of zero cleavage.
Quartz does not have cleavage, but they do have a fracture to them, leaving a jagged edge. Fracture occurs in the absence of cleavage. Most minerals fractures are irregular. Some fracture smoothly like glass.
Conchoidal fractures
produce knife-sharp edges.
Mineral Calcite
The mineral calcite will fizz when in contact with a weak acid (HCl). Only the mineral calcite will behave this way.
Calcite is the most common carbonate mineral. Calcite is known for fizzing in a weak acid.
Halite
Taste Salty
4000 identified minerals
Only a handful of them are actually common.
Silicates
Silicon (27.7%) and oxygen (46.6%) are the two most abundant elements in the earth’s crust. These 2 elements make up a group of minerals called the silicates.
silicon oxygen tetrahedron
Silicate minerals consist of oxygen and silicon atoms arranged into a silicon-oxygen tetrahedron. 1 silicon atom is surrounded by 4 oxygen atoms.
Igneous rocks
Igneous rocks form from the cooling of magma (inside the earth) or lava (surface of the earth)
Silicate minerals are the building blocks for all igneous rocks around the world. Most magmas generate only a few minerals.