Minerals

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

Naturally-formed solid substance with a crystal structure

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

All:

Are formed by natural processes.

Are NOT alive and NEVER were alive

Have a definite volume and shape

Are elements or compounds with a unique chemical makeup

Are made up of particles that are arranged in a pattern that is repeated over and over (called a CRYSTAL )

Watch “Crystals” by Brainpop… .What element are diamonds made from? . What do all crystals have in common?

Watch “Crystals” by Brainpop…

.What element are diamonds made from?

. What do all crystals have in common?

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

Minerals are grouped by the elements they are made of.

MICA Quartz Quartz, mica Contain oxygen & silica The most abundant group of minerals Silicates Examples Characteristics Mineral Group

Contain oxygen & silica

The most abundant group of minerals

Silver Gold Ruby Iron Copper Diamond iron, copper, gold, silver, diamonds, rubies Make up only 5% of the Earth’s crust Include some of the most important minerals Non-Silicates Examples Characteristics Mineral Group

Make up only 5% of the Earth’s crust

Include some of the most important minerals

Calcite with Duftite inclusions Calcite (CaCO 3 ) Carbon & oxygen and a positive ion, such as calcium Carbonates Examples Characteristics Mineral Group

Carbon & oxygen and a positive ion, such as calcium

Hematite (Fe 2 )O 3 Metallic ion and oxygen Oxides Examples Characteristics Mineral Group

Metallic ion and oxygen

Galena (PbS) Sulfur and a metallic ion Sulfides Examples Characteristics Mineral Group

Sulfur and a metallic ion

Barite on Calcite BaSo4 / CaCO3 Barite BaSo4 Barite (BaSO 4 ) Metallic ion, Sulfur & oxygen Sulfates Examples Characteristics Mineral Group

Metallic ion, Sulfur & oxygen

Gold (Au), Diamond (C), Silver (Ag) Single elements Native Elements Examples Characteristics Mineral Group

Single elements

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

1) Cooling of magma (hot, liquid rock and minerals inside the earth (from the mantle))

Fast Cooling = No Crystals (mineraloids)

Medium Cooling = small 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 vary with the type of impurities

Color

Can be misleading

Can vary with the type of impurities

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

Luster

Surface reflection

metallic = shiny like metal

non-metallic = dull, non-shiny surface

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 streak can be different than the mineral Minerals must be softer than the streak plate

Streak

The color of the powdered form of the mineral

The color of the streak can be different than the mineral

Minerals must be softer than the streak plate

Streak…can help identify quartz BUT... http://www.childrensmuseum.org/geomysteries/cube/b3.html

Physical Properties of Minerals (can be used to identify the mineral) Hardness How easily a mineral scratches materials Mohs Hardness Scale 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)

Hardness

How easily a mineral scratches materials

Mohs Hardness Scale

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)

Find out more… “ Electronic” Hardness Test http://www.childrensmuseum.org/geomysteries/cube/b2.html

“ Electronic” Hardness Test

http://www.childrensmuseum.org/geomysteries/cube/b2.html

Physical Properties of Minerals (can be used to identify the mineral) Cleavage & Fracture The way the mineral breaks 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

Cleavage & Fracture

The way the mineral breaks

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

Cleavage or Fracture? 1. 4. 3. 2.

Physical Properties of Minerals (can be used to identify the mineral) Other Properties Specific gravity (*excellent clue to mineral’s identity) Attraction to magnets Bending of light Reaction with hydrochloric acid Smell & taste http://www.childrensmuseum.org/geomysteries/cube/b4.html

Other Properties

Specific gravity (*excellent clue to mineral’s identity)

Attraction to magnets

Bending of light

Reaction with hydrochloric acid

Smell & taste

Watch Brainpop—“Mineral Identification” . If a mineral can scratch your fingernail, the mineral is _______________ than your fingernail. 2. What is luster?

Watch Brainpop—“Mineral Identification”

. If a mineral can scratch your fingernail, the mineral is _______________ than your fingernail.

2. What is luster?

Watch Classifying Minerals Clip

What is a gem? A Mineral OR Rock that has value Rare ! Sometimes polishing or cutting will add value

A Mineral OR Rock that has value

Rare !

Sometimes polishing or cutting will add value