What is a Mineral? Naturally-formed solid substance with a crystal structure Naturally-formed solid substance with a crystal structure Pyromorphite

What do all minerals have in common? All: 1. Are formed by natural processes. 2. Are NOT alive and NEVER were alive- ”inorganic” 3. Have a definite volume and shape 4. Are elements or compounds with a unique chemical makeup 5. Are made up of particles that are arranged in a pattern that is repeated over and over (called a CRYSTAL)

Groups of Minerals Minerals are grouped by the elements they are made of. Minerals are grouped by the elements they are made of. Amethyst Beryl (Emerald) Calcite

Metallic Minerals Many minerals are classified as metals. These minerals have several properties in common, such as luster, hardness, ductility (can be pulled into a wire without breaking), malleability (can be hammered or pressed into a thin sheet with out breaking), and conductivity (can transfer electricity). Some examples are : gold, silver, copper, mercury, lead, iron, nickel, tin, and uranium. Many minerals are classified as metals. These minerals have several properties in common, such as luster, hardness, ductility (can be pulled into a wire without breaking), malleability (can be hammered or pressed into a thin sheet with out breaking), and conductivity (can transfer electricity). Some examples are : gold, silver, copper, mercury, lead, iron, nickel, tin, and uranium.

Nonmetallic Minerals Nonmetallic minerals form a large group of minerals which contain no metal or are not used for the metals they may contain. Nonmetallic minerals form a large group of minerals which contain no metal or are not used for the metals they may contain. The world’s most common minerals belong to this group. Some are: sulfur, graphite, halite, gypsum, talc, and quartz. The world’s most common minerals belong to this group. Some are: sulfur, graphite, halite, gypsum, talc, and quartz.

Gems Gems are the most prized and famous of all minerals. Gems are the most prized and famous of all minerals. A gem is a valuable, highly priced minerals that is rare, or is difficult to obtain. A gem is a valuable, highly priced minerals that is rare, or is difficult to obtain. Diamonds, emeralds, rubies, and sapphires stand out as true gems. Diamonds, emeralds, rubies, and sapphires stand out as true gems. Other stones are classified as semiprecious and ornamental stones. Other stones are classified as semiprecious and ornamental stones.

Rock-forming Minerals Most rocks contain several minerals, or were formed form older rocks in which these minerals were present. Most rocks contain several minerals, or were formed form older rocks in which these minerals were present. These minerals are an important part of the earth’s crust. These minerals are an important part of the earth’s crust. Most of these minerals contain metals, but they are not metallic ores. Most of these minerals contain metals, but they are not metallic ores.

How do minerals form? 1) Cooling of magma (hot, liquid rock and minerals inside the earth (from the mantle)) 1) Cooling of magma (hot, liquid rock and minerals inside the earth (from the mantle)) Fast Cooling = No Crystals (mineraloids) Fast Cooling = No Crystals (mineraloids) Medium Cooling = small crystals Medium Cooling = small crystals Slow Cooling = large crystals Slow Cooling = large crystals

How do minerals form? 2) Elements dissolved in liquids (usually water) 2) Elements dissolved in liquids (usually water)

Physical Properties of Minerals (can be used to identify the mineral) Color Can be misleading Can be misleading Can vary with the type of impurities Can vary with the type of impurities

Physical Properties of Minerals (can be used to identify the mineral) Luster Surface reflection Surface reflection metallic = shiny like metal metallic = shiny like metal non-metallic = dull, non-shiny surface non-metallic = dull, non-shiny surface Pyrite has a metallic luster Calcite has a non-metallic luster

Physical Properties of Minerals (can be used to identify the mineral) Streak The color of the powdered form of the mineral The color of the powdered form of the mineral The color of the streak can be different than the mineral The color of the streak can be different than the mineral Minerals must be softer than the streak plate Minerals must be softer than the streak plate

Streak…can help identify quartz

Physical Properties of Minerals (can be used to identify the mineral) Hardness How easily a mineral scratches materials How easily a mineral scratches materials Mohs Hardness Scale Mohs Hardness Scale Scale from 1 (softest) to 10 (hardest) Scale from 1 (softest) to 10 (hardest) Test by seeing if the mineral can scratch different objects (like human fingernail, copper, penny, glass, steel file) Test by seeing if the mineral can scratch different objects (like human fingernail, copper, penny, glass, steel file)

Find out more… “Electronic” Hardness Test “Electronic” Hardness Test steries/cube/b2.html steries/cube/b2.html

Physical Properties of Minerals (can be used to identify the mineral) Cleavage & Fracture The way the mineral breaks The way the mineral breaks Cleavage—minerals break along smooth, flat surfaces and every fragment has the same general shape Cleavage—minerals break along smooth, flat surfaces and every fragment has the same general shape Fracture—minerals that break at random with rough or jagged edges Fracture—minerals that break at random with rough or jagged edges

Cleavage or Fracture?

Physical Properties of Minerals (can be used to identify the mineral) Other Properties Specific gravity (*excellent clue to mineral’s identity) Specific gravity (*excellent clue to mineral’s identity) Attraction to magnets Attraction to magnets Bending of light Bending of light Reaction with hydrochloric acid Reaction with hydrochloric acid Smell & taste Smell & taste

Three common Earth resources that have importance based on their properties are: 1. Minerals: Natural, solid materials found on Earth that are the building blocks of rock; each has a certain chemical makeup and set of properties. 2. Ores: minerals that are mined because they contain useful metals or nonmetals 3. Fossil Fuels: Natural fuels that come from the remains of living things; fuels give off energy when they are burned.