Minerals Physical Properties
Terms to know:
Atom- subatomic particles such as elements, protons and neutrons
Electron- negative charge
Neutron- neutral, no electrical charge
Element- atoms are defined by the number of protons
Proton- positive charge
Streak color- take mineral and rub it against a streak plate leaving behind a powder and the color of that powder that is the streak color
Luster- fundamental property of minerals, metals
Specific gravity- density, different minerals have different densities
Non-metallic luster- do not appear as metal (ex. Copper, Gold and Quartz) Cleavage- ability of a mineral to break along smooth parallel surfaces; shiny Fracture- mineral that breaks in non- smooth rough surfaces (ex. Broken glass) Crystal form- how the mineral grows; constructive property
We also discuss several other topics like How do you find the primary sequence of a protein?
Polymorph- same chemistry but different in crystalline structure
Metallic luster- minerals that look like a metal, shiny
Hardness- minerals resistance to being scratched
Medium- steel nail=5.5
Hard- cannot scratch
Conchoidal fracture- rough and irregular break Basal- one direction, minerals break out into little sheets Prismatic- two directions, form prisms
Rhombic- three directions not at 90 degrees Cubic- three directions at 90 degrees
Octahedral- four directions, form triangles
Concepts to know:
1. Know what an atom and element is
Atom- subatomic particles such as elements, protons and neutrons Element- different type of atoms, atoms are defined by the number of protons
2. Know the chemical symbol for the twelve most common elements in minerals H- Hydrogen Ca- Calcium C- Carbon K- Potassium N- Nitrogen Al- Aluminum O- Oxygen Si- Silicon Na- Sodium Fe- Iron Mg- Magnesium Cl- Chlorine If you want to learn more check out In which style of eating does quality matter?
3. What is the complete definition of mineral
1. Naturally occurring We also discuss several other topics like What is the definition of sexual orientation?
4. Crystalline structure
5. Definite chemistry
4. Know the complete definition of luster
Luster- fundamental property of minerals
1. Metallic luster- minerals that look like a metal; shiny
2. Non- metallic luster- do not look like a metal
5. Why is color a poor property to use when identifying minerals
It is a horrible property because the color of a mineral tells you nothing over the minerals. For example, Quartz has over 120 different colors
6. What is the difference between color and streak color
With color it is all about impurities, one can’t tell nothing from it. With streak color one can tell by the powder that’s left behind and usually is always the same. It is only useful for certain minerals that have a metallic luster.
7. How do geologists determine the hardness of a mineral
By looking at the minerals resistance to being scratched
8. Know the Mohs Hardness Scale
8. Topaz HARD
4. Fluorite STEEL NAIL = 5.5
3. Calcite MEDIUM
2. Gypsum FINGERNAIL = 2.5
1. Tale SOFT
9. What is mineral cleavage? How is it different from fracture?
Mineral cleavage has the ability to break along smooth parallel surfaces. It is difference from fracture because with fracture the minerals break in a non-smooth rough surfaces. We also discuss several other topics like What are the components of religion?
10. What conditions are needed for a crystal to grow large? How is crystal form different from cleavage?
Space and Time is what’s needed for the mineral to grow. It is different from cleavage because with cleavage it is a destructive property and cleavage is a constructive property
11. What are some other properties that can be used to identify minerals? a. Specific gravity (ex. Density, metallic luster is heavy such as gold and with non-metallic luster it has a low density)
b. Magnetism (ex. Is it magnetic)
c. Reaction to acid (ex. calcite)
d. Distinctive smell (ex. Sulfur smells like Rotten egg)
e. Taste (ex. Halite tastes salty)
Mineral Groups Ch. 2
Terms to know:
Silicates: Rock-forming minerals, made out of Silicon and Oxygen
Silicon-oxygen Tetrahedron: silicon and oxygen have an arrangement which are 4 oxygen atoms (-2) & 1 silicon atom (+4) We also discuss several other topics like A priori means what?
Ionic Bonding: Positive attracts negative and can be brought together creating a bond (weak; cleavage)
Convalent Bonding: Sharing Oxygen atoms (strong; fracture)
Ions: group of atoms formed due to loss or gain of one or more electrons Cations: positive charge
Ferromagnesium Silicates: Mg, Fe, Si, O (dark appearance)
Non-Ferromagnesian Silicates: Na, K, Ca, Al, Si, O (light appearance) Non-Silicates: Have everything except Silicates, 6 different groups Don't forget about the age old question of How do mollusca acquire food?
Carbonates: (cation + C + O)
Sulfates:(cation + S + O)
Halides: (Cation + Anion)
Oxides: (Cation + O)
Sulfides: (Cation + S)
Native Elements: consist of one single element (pure compound) Diamond-Carbon, Gold, Silver, Platinium
Concepts to Know:
1. What type of bonding is stronger? Covalent or Ionic? And why?
Covalent bonding is stronger because they share one oxygen atom between two tetrahedra. Has a fracture surface making it a hard mineral to break because it is strong-bonded together
2. How is bonding related to the two groups of silicate minerals?
They both include Silicons and Oxygen
3. Know the mineral names for the ferromagnesian (e.g. biotite) and non-ferromagnesian (e.g. quartz) silicates.
Ferromagnesium Silicates Minerals:
Non-Ferromagnesian Silicates Minerals:
4. Know an example of a mineral for each of the non-silicate groups (e.g. native elements). Also know about the chemistry of each of the 6 non-silicate groups.
1. Carbonates (Cation+Carbon+Oxygen) Minerals: Calcite, fine it in marble and building stones
2. Sulfates (Cation+Sulfur+Oxygen) Minerals: Gypsum, used in sheetrock 3. Halide (Cation+Anion) Minerals: Halite (salt) and Fluorite
4. Oxides (Cation+Oxygen) Minerals: Magnetite and Hematite
5. Sulfides (Cation+Sulfur) Minerals: Pyrite (fools gold)
6. Native Elements- only consist of a single element and it’s a pure compound, for example diamond is made out of carbon only. Other elements are gold, silver, copper, platinum and silver
Terms to Know: *definitions are the order of the rock cycle*
Magma: molten rock, below surface (never makes it to the earth’s surface) Lava: molten rock, on surface (flows onto or explodes onto the earth’s surface) Crystallization: former into a solid
Igneous Rock: forms from the cooling and crystallization of molten rock Weathering: slowly breaks down these rocks into smaller pieces (series of chemical and physical processes)
Transportation: pieces get picked up and moved through water, winds, glaciers, waves, and tides
Deposition: material gets deposited into a place
Sediment: loose material that either compacted or cemented
Lithification: turns into sedimentary rock (compaction and cementation) Sedimentary Rock: forms form either pieces of preexisting rocks or the hard parts of once living plants and animals.
Metamorphism: subject rock to high temperatures and pressure that chemical reactions will occur
Metamorphic Rock: forms from either under intense heat and pressure or by intense heat and volatiles escaping from an ascending magma body
Melting: becoming liquified by heat
Concepts to Know:
1. Know the outside loop of the rock cycle.
2. What can happen to any rock exposed at the surface? Any rock at the surface can undergo weathering and can make sediment.
3. Can any rock undergo melting to form magma? Yes, all! Any rock can undergo melting when temperatures are high
4. Can any rock undergo metamorphism? Yes, all!
Terms to know:
Magma- complex material, mixture of solid, liquid and gas
Lava- gentle eruption, flows out onto the surface
Extrusive- surface, cools rapidly-large crystals
Intrusive- below surface, cools slowly- small or no crystals
Phaneritic- all large crystals
Glassy- has no minerals, no crystals
Rhyolite- violent eruption including pyroclastic, part of the caldera volcano Diorite- phaneritic texture, medium color (both ferromagnesian and non ferromagnesian) Pyroclastic- violent volcano eruption, erupts billions of pieces into the atmosphere Gabbro- phaneritic texture, dark color (ferromagnesium)
Obsidian- glassy texture
Tuff- a light rock formed by volcanic ash
Porphyritic- has small crystals, but also a mixture of a few large crystals Andesite- can be gentle or violent and is part of the composite cone volcano Basalt- gentle eruption, is part of the shield volcano
Granite- phaneritic texture, light color (non-ferromagnesian)
Groundmass- refined grains in a rock, small crystals
Phenocrysts- form in intrusive sediment, large crystals
Concepts to know:
1. What makes up magma/lava?
a. Molten rock
b. Solid rock fragments- Crystals
c. Dissolved gas- water vapor and carbon dioxide
2. How does the location in which the molten rock material influence the texture of the igneous rock?
Texture is controlled by how fast the molten material cools. Location controls texture and what the rock will look like.
Magma- Intrusive, cool slowly; larger crystals
Lava- Extrusive, cool rapidly; smaller or no crystals
3. What are the different types of textures that can be exhibited by an igneous rock? Phaneritic- all large crystals
Porphyritic- it's complicated because it has small crystals, but can sometimes have a few large crystals
Glassy- rock cools extremely rapidly, absolutely no crystals (ex. obsidian) 4. What is the special significance of a porphyritic texture?
Groundmass- refined grains in a rock, extrusive-small crystals
Phenocrysts- form in intrusive sediment, have a complex cooling history-large crystals
NOTE: You got one above ground and below ground that is why porphyritic is complicated and special
5. Know the classification of igneous rocks
Augite, Ca-rick, plagioclase
Biotite, Na-rich plagioclase,
NOTE: Ferromagnesium- Dark color , its SiO2 is low
Non-Ferromagnesian- Light color, its SiO2 is high
Both ferromagnesian and non-ferromagnesian are both mixed of dark and light, SiO2 is medium
6. What type of silicate minerals ferromagnesian or non-ferromagnesian are associated with gabbro; diorite and granite?
Gabbro- ferromagnesian, dark color
Diorite- mixture of both ferromagnesian and non-ferromagnesian, medium color Granite- non-ferromagnesian, light color
7. What is the significance of a glassy texture?
It has no crystals meaning no crystalline structure, making them to never have order, they get locked in. Glass has no minerals.
Terms to know:
Detrital- made up of bits of pieces left after weathering
Non-Detrital- pieces of rock go off into the ocean and come back together, get produced Clay- small size sediment
Silt- small size sediment
Sand- medium size sediment
Gravel- large size of sediment
Lithification- destruction through compaction and cementation
Limestone- forms in marine environment, dissolution
Rock Gypsum- gypsum
Rock Salt- halite
Coal- plant material, organic
Cross-Bedding- dune, form by wind but sometimes also by water
Ripple Marks- formed in sand by wind, but commonly formed by water has curvy lines. Can get fossilized
Mud Cracks- occurs when mud dries out and creates cracks on land
Fossils- evidence of past life
Dissolution- attacking a solid at the atomic level and the water molecules kick off ions and surround those ions completely with water molecules (EX. limestone)
Hydration- mineral H2O, clay mineral
Oxidation- mineral Fe + O2, Oxide + Ions
Terrestrial- land (EX. rivers, lakes, glaciers, sand domes) Transitional- beach
Marine- continental shelf, reef, deep marine
Mechanical Weathering- process of breaking big rocks into smaller pieces Chemical Weathering- decomposition of rocks due to water
Concepts to Know:
1. Know the difference between chemical and mechanical weathering?
Two basic types of weathering:
1. Frost wedging: frozen water getting into the cracks of the rock eventually breaking it into smaller pieces.
2. Unloading: rock that is formed deep under the surface known as sheeting. Over geological time the rocks above get removed and those below the surface are now above.
3. Thermal expansion: heating rock causes expansion when getting hot that will eventually be broken down into small pieces.
4. Biological weather: trees growing into rocks.
1. Dissolution: it attacking a solid at the atomic level and the water molecules kick off ions and surround them within water molecules. Ex. coffee, tea sugar
molecules get surrounded by the water and get dissolved.
2. Hydration: take a mineral then add water which gives clay(mud) minerals liberating ions.
3. Oxidation: Mineral Fe, adding oxygen will get oxide plus ions.
2. What by-products of weathering are used to make sedimentary rocks? These are the raw materials-
● Quartz is the major by product, resist weathering
● Orthoclase/Plagioclase left over after weathering
● Clay minerals, biggest by product
● Oxides- hematite
Cations: sodium, potassium, calcium, and magnesium.
Anions: chlorine, carbonate, and sulfate.
3. What is the difference between a detrital and non-detrital sedimentary rock? Detrital: Sediment that is made up of bits and pieces of minerals that are left after weathering and put together to make Detrital rocks
Non-Detrital: mostly made up of ions that get liberated, made of different by products of weather.
4. What are the different types of sediment and what is the basis for the classification of these different sediment types?
Detrital sedimentary Rocks: is all about the size of the sediment
Conglomerate (loose gravel) , Breccia (grounded pebbles)
Sandstone (made up of
Shale (plant fossil)
5. What is the difference between a sediment and sedimentary rock?
Sediment- composed of weathered pieces of rock
Sedimentary Rock- forms when sediments are compacted and cemented together (liquification)
6. What is the bedrock of Laredo?
In laredo we have both sandstone and shale
7. How does a non-detrital sedimentary rock form? Know some examples of this rock type. Composition, taking the ions into liberation and then putting them together to form a rock. Ex.
● Limestone, is form of calcite usually found in sea shells
● Chert, is made mostly of the mineral quartz there can be dozens of chert ● Rocksalt, made of the mineral halite found in places that are very hot and have high evaporation.
● Rock gypsum, is made of the mineral gypsum
● Coal, is made of plant material not made of minerals
8. Know the basic depositional environments where sediment can be deposited. Sedimentary environment 3 basic
1. Terrestrial (land): Rivers, lakes, glaciers, sand dunes-desert
2. Transitional: the beach,
3. Marine: on the continental shell, reef, deep marine thousands of feet down below sea level.
9. What features can help you interpret the depositional environment of a sedimentary rock? Sedimentary structures
➔ Cross bedding: found in dunes made of wind and water.
➔ Ripple Marks: sediment that has been moved, from in wind commonly found in water. ➔ Mud cracks: deposited on land where mud will dry and form the cracks ➔ Fossil: evidence for past life.
10. What is sorting? How can it be used to determined what mechanism transported the sediment? Be able to describe a well versus poorly sorted sediment.
Second clue called Sorting, is a measure of the variability in particle size. ● Well sorted: particles all are the same size, you get them by running water or wind (waves and tides)
● Poorly sorted: particles varies in size, have silt, clay, gravel and glaciers they push the sediment up
11. What can mineral composition tell you about the sedimentary environment? Composition:
● Rock salt gypsum-hot, arid, evaporites
● Limestone- Marine,warm,
● Coal: warm, humid, swamps tropical type of setting to form coal.
Terms to know:
Protolith- Metamorphic rocks form from a preexisting rock that has been subjected to intense heat, pressure, or chemically active uids and gases (such as volatiles from a magma body) Foliated Texture- is a rock where the minerals have a common alignment in the same direction Metamorphism- is change, the change can be either physical you can change the texture of the rock or chemical reaction, it changes the minerals that it has
Marble- nonfoliated metamorphic rocks, as the coase calcite crystals will not display any form of mineral alignment
Slate- protolith of shale, its metamorphic grade is low
Non-Foliated Texture- a texture resulting from an absence or pressure and, hense, an absence or any mineral alignment or banding
Regional Metamorphism- Metamorphism that is driven by increasing heat and pressure Quartzite- they appear to be hard, strong rocks but are composed entirely of calcite (which has a hardness of 3 and can easily be scratched by a steel nail)
Metamorphic Grade- intensity of metamorphism
Schist- protolith of shale, its metamorphic grade is medium to high
Contact Metamorphism- occurs when a hot, volatile-rich magma body comes in contact with colder surrounding crust
Gneiss- protolith of granite and with high intensity of metamorphism it creates gneiss rock
Concepts to Know:
1. In general, what conditions are necessary for metamorphism to occur? ● Heat- Metamorphism happens during hot temperatures, but is not high enough because it will could create magma
● Pressure- miles below the surface
● Chemically reactive fluids- such as water and carbon dioxide these fluids can catalyze chemical reactions and minerals will change giving you a metamorphic rock. 2. What type of texture is associated with contact metamorphic rocks?
● Big magma chamber- is producing heat that will bake the rock around it. ● Limited pressure, there is not much pressure
● Since there is no pressure there is no minerals lining up known as non-foliated texture. 3. What type of texture is associated with regional metamorphic rocks?
● Period of mountain building- ex. Two continents collide and the earth is under a lot of pressure and as a result of them being built they are buried to great depths and subjected to high temperature/pressure.
● High pressure- Under the mountains rocks go under pressure creating new rocks such as gneiss and line up in one direction.
● Foliated texture- is a rock where the minerals have a common alignment in the same direction.
4. What are the protoliths associated with a marble, quartzite, schist, and gneiss? Non foliated
● Protolith: the rock that existed before metamorphism
1. Sandstone gets subjected into high temperatures known as quartzite
2. Limestone after magma is marble
Foliated metamorphic rocks
Medium and High
● Protolith: metamorphic grade it's the intensity of metamorphosis
● Shale (sedimentary): low grade metamorphism transform into the rock call slate ● Shale after being in high temperature it becomes into schist
● Granite: it takes high grade metamorphism to do anything to granite and transforms into gneiss