Chapter 2 Minerals

Vocabulary  Element  Atomic number  Energy level  mass number  Compound  Chemical bond  Ion  Ionic bond  Covalent bond  Fracture  Density  Element  Atomic number  Energy level  mass number  Compound  Chemical bond  Ion  Ionic bond  Covalent bond  Fracture  Density  Metallic bond  Mineral  Silicate  Silicon-oxygen tetrahedron  Streak  Luster  Crystal form  Hardness  Mohs scale  cleavage

I. Elements and the Periodic Table A.An element is a substance that cannot be broken down into simpler substances by chemical or physical means. 1.There are 112 known elements, 92 occur naturally, while others are man made. 2. Only eight elements make up the Earth’s crust. 1.Oxygen, Silicon, Aluminum, Iron, Calcium, Sodium, Potassium, Magnesium 3.Organized for there properties. a.Rows are called periods b. Columns are called groups. A.An element is a substance that cannot be broken down into simpler substances by chemical or physical means. 1.There are 112 known elements, 92 occur naturally, while others are man made. 2. Only eight elements make up the Earth’s crust. 1.Oxygen, Silicon, Aluminum, Iron, Calcium, Sodium, Potassium, Magnesium 3.Organized for there properties. a.Rows are called periods b. Columns are called groups.

II. Atoms A.Ions are charged B.An atom is the smallest particle of matter that contains the characteristics of an element. 1.Center is known as the nucleus. a.Contains protons and neutrons 1.Protons are positive, and has about the same mass as the neutron. 2.The atomic number is the number of protons that are located in that element. 3.Neutrons are neutral 2.Electrons are negative charged and are located around the outside of the nucleus. a.They are the smallest particles in the atom. b.They are located in energy levels, which they move up and down when they get excited. A.Ions are charged B.An atom is the smallest particle of matter that contains the characteristics of an element. 1.Center is known as the nucleus. a.Contains protons and neutrons 1.Protons are positive, and has about the same mass as the neutron. 2.The atomic number is the number of protons that are located in that element. 3.Neutrons are neutral 2.Electrons are negative charged and are located around the outside of the nucleus. a.They are the smallest particles in the atom. b.They are located in energy levels, which they move up and down when they get excited.

III. Why Atoms bond A.A compound is a substance that consists of two or more elements that are chemically combined in specific proportions. 1.They form when atoms are more stable. 2.They want to complete their outer shells by obtaining 8 electrons on the outside shell. A.A compound is a substance that consists of two or more elements that are chemically combined in specific proportions. 1.They form when atoms are more stable. 2.They want to complete their outer shells by obtaining 8 electrons on the outside shell.

IV. Types of Chemical Bonds A.Ionic Bond form between positive and negative ions. 1.They are rigid solids with high melting and boiling points. 2.Poor conductors of electricity. 3.Usually consist of groups 1 and 2 with elements from groups 16 and 17. A.Ionic Bond form between positive and negative ions. 1.They are rigid solids with high melting and boiling points. 2.Poor conductors of electricity. 3.Usually consist of groups 1 and 2 with elements from groups 16 and 17.

B. Covalent Bonds form when atoms share electrons. 1. They have low melting and boiling points. C. Metallic Bonds form when electrons are shared by metal ions. 1. Can be easily shaped. B. Covalent Bonds form when atoms share electrons. 1. They have low melting and boiling points. C. Metallic Bonds form when electrons are shared by metal ions. 1. Can be easily shaped.

V. Minerals A.A mineral is a naturally occurring, inorganic solid with an orderly crystalline structure and a definite chemical composition. B.All have the following characteristics 1. Naturally occurring 2. Solid substance 3. Orderly crystalline structure 4. Definite chemical composition 5. Generally considered inorganic. A.A mineral is a naturally occurring, inorganic solid with an orderly crystalline structure and a definite chemical composition. B.All have the following characteristics 1. Naturally occurring 2. Solid substance 3. Orderly crystalline structure 4. Definite chemical composition 5. Generally considered inorganic.

C. How minerals form 1. There are four major processes by which minerals form: a. Crystallization from magma 1. Rich in iron, calcium, and magnesium start then at end, sodium, potassium, and aluminum form. b. Precipitation 1. Water on Earth contains dissolved substances. Evaporation leaves these behind to condense into minerals. C. How minerals form 1. There are four major processes by which minerals form: a. Crystallization from magma 1. Rich in iron, calcium, and magnesium start then at end, sodium, potassium, and aluminum form. b. Precipitation 1. Water on Earth contains dissolved substances. Evaporation leaves these behind to condense into minerals.

c. Hydrothermal Solutions 1. Very hot solution, temps. Between 100 o C and 300 o C, come in contact with other minerals and then you get a chemical reaction. d. Pressure and Temperature 1. Minerals are subjected to extreme temperature and/or pressure changes. c. Hydrothermal Solutions 1. Very hot solution, temps. Between 100 o C and 300 o C, come in contact with other minerals and then you get a chemical reaction. d. Pressure and Temperature 1. Minerals are subjected to extreme temperature and/or pressure changes.

D. Properties of Minerals. 1. Color a. The first thing to notice, small amounts of different elements can g ive the same mineral different colors. 2. Streak a. The color of a mineral in its powdered form. 3. Luster a. Is used to describe how light is reflected from the surface of a mineral. D. Properties of Minerals. 1. Color a. The first thing to notice, small amounts of different elements can g ive the same mineral different colors. 2. Streak a. The color of a mineral in its powdered form. 3. Luster a. Is used to describe how light is reflected from the surface of a mineral.

4. Crystal Form a. This is the visible expression of a mineral’s internal arrangement of atoms. 5. Hardness (Mohs Scale) a. 1 (softest) - 10 (hardest) 6. Cleavage a. The tendency of a mineral to cleave, or break along flat even surfaces. 7. Fracture a. Minerals that do not show cleavage when broken, but rather break unevenly. 4. Crystal Form a. This is the visible expression of a mineral’s internal arrangement of atoms. 5. Hardness (Mohs Scale) a. 1 (softest) - 10 (hardest) 6. Cleavage a. The tendency of a mineral to cleave, or break along flat even surfaces. 7. Fracture a. Minerals that do not show cleavage when broken, but rather break unevenly.

8. Density a. The property of all matter that is the ratio of an objects mass to its volume. D=M/V g/cm 3 E.Distinctive properties 1.Talc=Soapy2. Graphite=write 3. Magnitite=Magnetic4.Carbonate=fizz 8. Density a. The property of all matter that is the ratio of an objects mass to its volume. D=M/V g/cm 3 E.Distinctive properties 1.Talc=Soapy2. Graphite=write 3. Magnitite=Magnetic4.Carbonate=fizz

VI. Mineral Groups A.Carbonate Minerals. 1. The carbonate groups is made of one carbon atom combined with three oxygen atoms, and has a negative charge of two. 2. The rocks limestone and marble are made almost entirely of carbonate minerals. A.Carbonate Minerals. 1. The carbonate groups is made of one carbon atom combined with three oxygen atoms, and has a negative charge of two. 2. The rocks limestone and marble are made almost entirely of carbonate minerals.

3. Types of Carbonates a. The most common carbonate mineral is calcite. 1. Has three prefect cleavages that meet at oblique angels, and can be easily identified using the acid test. b. Dolmite 1. Is a calcium magnesium carbonate, that has a hardness of and cleaves into rhombs. 3. Types of Carbonates a. The most common carbonate mineral is calcite. 1. Has three prefect cleavages that meet at oblique angels, and can be easily identified using the acid test. b. Dolmite 1. Is a calcium magnesium carbonate, that has a hardness of and cleaves into rhombs.

Calcite Dolmite

B. Iron Oxide and Sulfide minerals 1. An oxide is a mineral consisting of a metal element combined with oxygen. 2. Types of minerals. a. Hematite is the most common iron oxide mineral, with a hardness of 5-6 and is red with an earthy luster, and will have a red-brown streak. b. Magnetite is a black magnetic iron oxide, with a hardness of and is highly magnetic. B. Iron Oxide and Sulfide minerals 1. An oxide is a mineral consisting of a metal element combined with oxygen. 2. Types of minerals. a. Hematite is the most common iron oxide mineral, with a hardness of 5-6 and is red with an earthy luster, and will have a red-brown streak. b. Magnetite is a black magnetic iron oxide, with a hardness of and is highly magnetic.

Magnetite

3. A sulfide is a metal element combined with sulfur. 4. Type of sulfide minerals. a. Pyrite is the most common sulfide mineral and has a color from pale brass to golden-yellow with a hardness of 6. C. Silicate Minerals 1. More than 90 percent of the minerals in Earth’s crust are made of silicates. 2. They consist of four oxygen atoms bounded to a central silicon atom. 3. A sulfide is a metal element combined with sulfur. 4. Type of sulfide minerals. a. Pyrite is the most common sulfide mineral and has a color from pale brass to golden-yellow with a hardness of 6. C. Silicate Minerals 1. More than 90 percent of the minerals in Earth’s crust are made of silicates. 2. They consist of four oxygen atoms bounded to a central silicon atom.

Pyrite

3. Examples of silicate minerals. a. Quartz is made entirely of silica and has a glassy or greasy luster. It fractures are irregular, with a hardness of 7. It is colorless, but may have some pink, purple, brown or gray. b. Feldspar makes up 60 percent of the crust, and had two directions of cleavage with a hardness of Examples of silicate minerals. a. Quartz is made entirely of silica and has a glassy or greasy luster. It fractures are irregular, with a hardness of 7. It is colorless, but may have some pink, purple, brown or gray. b. Feldspar makes up 60 percent of the crust, and had two directions of cleavage with a hardness of 6.

1. There are two types of feldspar. A. Potassium feldspar. 1. Most common and known as orthoclase. Has a white or cream color with two cleavage surfaces that meet at a right angle. B. Sodium-calcite feldspar 1. Known as plagioclase and has a white to gray color. It also has two cleavage surfaces that meet at slightly less than a right angle. 1. There are two types of feldspar. A. Potassium feldspar. 1. Most common and known as orthoclase. Has a white or cream color with two cleavage surfaces that meet at a right angle. B. Sodium-calcite feldspar 1. Known as plagioclase and has a white to gray color. It also has two cleavage surfaces that meet at slightly less than a right angle.

Potassium Feldspar Sodium Feldspar Quartz

C. Mica 1. A soft silicate that is found in many rocks that is flat, shiny and flakes are easily picked out of rocks. 2. Muscovite is silvery white, and Biotite is dark brown or black, both are soft and have a hardness of about 2.5 with perfect cleavages. D. Talc 1. The softest mineral with a white to grayish color and had one good cleavage. This mineral also has a soapy feel. C. Mica 1. A soft silicate that is found in many rocks that is flat, shiny and flakes are easily picked out of rocks. 2. Muscovite is silvery white, and Biotite is dark brown or black, both are soft and have a hardness of about 2.5 with perfect cleavages. D. Talc 1. The softest mineral with a white to grayish color and had one good cleavage. This mineral also has a soapy feel.

Muscovite Talc

E. Amphiboles 1. Forms long, needlelike crystals, and is the most common form of hornblende. 2.Usually dark green had has two good cleavages that meet at oblique angles. Has a hardness of 5-6. F. Pyroxenes 1. Augite is the most common member and is dark green brown, and has two good cleavages with a hardness between 5-6. E. Amphiboles 1. Forms long, needlelike crystals, and is the most common form of hornblende. 2.Usually dark green had has two good cleavages that meet at oblique angles. Has a hardness of 5-6. F. Pyroxenes 1. Augite is the most common member and is dark green brown, and has two good cleavages with a hardness between 5-6.

Hornblende Augite

G. Olivine 1. Is green and has a hardness around 6.5. H. Garnet 1. Is dark red to brown had has a hardness from I. Kaolinite 1.Usually is yellow with a hardness of 1- 2 and also has a greasy feel. G. Olivine 1. Is green and has a hardness around 6.5. H. Garnet 1. Is dark red to brown had has a hardness from I. Kaolinite 1.Usually is yellow with a hardness of 1- 2 and also has a greasy feel.

Olivine Garnet Kaolinite