Chapter 7 what Are Minerals? Lesson 1 Chapter 7 what Are Minerals?

Minerals Definition A mineral is a natural, solid substance that has a specific chemical makeup and a repeating styructure.

Minerals Every mineral can form as a crystal with a regular geometric shape.

Crystal Structure

Methods scientists use to identify minerals Color Streak Luster Hardness

Methods scientists use to identify minerals Color Minerals come in a rainbow of colors. However, color alone cannot be used to identify minerals as some minerals such as quartz come in different colors.

Methods scientists use to identify minerals Streak Color of powder left behind when a mineral is rubbed on an on a streak plate (unglazed tile) or a rough white tile Streak may be the same color as the mineral or different.

Methods scientists use to identify minerals Streak

Methods scientists use to identify minerals Luster The way a mineral reflects light. Many minerals have a metallic luster. Eg: gold, silver and copper Other minerals have a non metallic luster and can be describe as dull, glassy, pearly, waxy.

What are 3 visible properties of minerals?

What are 3 visible properties of minerals? Answer: Color Streak Luster

Methods scientists use to identify minerals Hardness Hardness is the measure of the ability of a mineral to resist being scratched.

Methods scientists use to identify minerals Hardness Hardness is the measure of the ability of a mineral to resist being scratched. Scientists use the Mohs scale.

Mohs scale

Methods scientists use to identify minerals Hardness Hardness is the measure of the ability of a mineral to resist being scratched. Scientists use the Mohs scale. Mohs scale rates minerals from softest (1) to hardest (10).

Methods scientists use to identify minerals Hardness Hardness is the measure of the ability of a mineral to resist being scratched. Scientists use the Mohs scale. Mohs scale rates minerals from softest (1) to hardest (10). Diamonds are a 10; no other minerals can scratch diamond. Diamond is 4 times harder than corundum (9).

Diamond

Methods scientists use to identify minerals Hardness is tested with common objects such as a finger nail, copper coin, glass, steel nail, pocket knife. 5.5 6 3.5 6.5 2.5 3.5

Methods scientists use to identify minerals Hardness Minerals can also be tested against each other.

Methods scientists use to identify minerals Hardness Hardness is tested with common objects such as fingernail, copper coin or wire, steel nail, and glass. Minerals can also be tested against each other.

Everyday uses Diamond is used as jewelry and to cut rocks and other very hard materials.

Everyday uses Sandpaper is made from a mineral called corundum because it is very hard. (9 on Mohs)

Everyday uses Graphite is very soft and is used in pencils.

Everyday uses Quartz is used to make glass.

Everyday uses Metals such as copper, silver, gold, and lead in their natural state are minerals. Copper ore Silver Gold Galena

Collector edition coins Everyday uses Collector edition coins Formerly used in coins Gold bars Jewelry Copper computer parts Silver tea service

Everyday uses Iron is used to make steel. Halite is rock salt.

Big ideas Minerals have visible properties such as streak, color, luster, and hardness. Minerals have many everyday uses. Minerals only form in nature from materials that were never alive.

Unique properties of minerals Some minerals such as calcite can bend light in a certain way when light enters it so that you see a double image.

Unique properties of minerals Some minerals are magnetic and can be used in compasses to guide our way.

Unique properties of minerals Some minerals can glow when exposed to UV light.

Unique properties of minerals Some develop an electric potential or electric charge when pressure or temperature applied to them.