Take home information from this section includes: - What is an element? - A substance that cannot be broken down into simpler substances by chemical or physical means known elements - 92 occur naturally, rest are made in the lab - Organized by properties into the Periodic Table

- What particles make up atoms? - Atoms are the smallest particles of matter - Made up of protons, neutrons, and electrons

What are Isotopes? - have the same number of protons but varying numbers of neutrons. - important because same element has different isotopes

What are compounds and why do they form? A compound consists of two or more elements that are chemically combined in specific proportions. Important because compounds have different properties than the elements that make them up

Mineral Characteristics natural inorganic solid definite composition crystal structure

4 major processes by which minerals form: 1. Crystallization from magma- cooling magma causes minerals to crystallize

2. Precipitation Minerals dissolve out of evaporated water; precipitated

Change in pressure and temperature cause an existing mineral to recrystallize while still solid Muscovite Talc

A hot mixtures of water with substances dissolved in them. When they come in contact with existing minerals- a chemical reaction occurs forming a new mineral Bornite

Minerals are grouped or classified based on their composition. There are 6 groups 1. Carbonates - contain carbon, oxygen, and one ore more metallic element

- formed from silicon and oxygen - elements combined to form a silicon tetrahedron, 1 silicon atom and 4 oxygen atoms - formed from cooling magma - either near the surface (few crystals) or deep below surface (larger crystals)

- Minerals that contain oxygen and one or more other element(s )

- Minerals containing sulfur Gypsum Pyrite

- minerals containing halogen ions plus one or more other elements Halite

Minerals that exist in a relatively pure form i.e. Gold, silver, copper Gold crystal structure

Mineral PROPERTIES are used to identify minerals based on specific characteristics Luster Streak Color Specific Gravity Cleavage & Fracture Hardness Magnetism Fluoresence

Streak color of a mineral in its powder form Color often not a good property for Iding

Luster how light is reflected from the surface of a mineral

Density= Mass (g) Volume (mL or cm 3 ) Density of water is 1 g/cm 3 Specific Gravity is a ratio, no units

Magnetism Magnetite Fluorescence Double Refraction Calcite Smell Sulfur