1. How to identify a mineral by its properties
Mineral ID
How to identify a mineral by its properties
Baker 7th grade science

2. Rocks vs. Minerals…. What’s the difference
Rocks vs. Minerals….. What’s the difference? All rocks are made of 2 or more minerals, but minerals are not made of rocks.
A mineral is a solid material found in nature that is not made up of living things. Minerals have a specific crystal form properties
There are about 2000 known minerals on earth.
Mineral is like an element – pure
Rock is like a compound- made up of 2 or more minerals

3. Today you will learn
Which mineral properties are most important in identification.
How mineral are identified by their properties.
Baker 7th grade science

4. A mineral’s appearance helps identify it.
In order to identify a mineral, you need to observe it properties – characteristics that help identify it.
There are 4 main properties that we
use to identify.
Color, Luster, Streak
and Hardness
Baker 7th grade science

5. Mineral Property #1 Color
Color is the first thing someone notices when they view a mineral.
The color of a mineral is based on its chemical composition
Color is one of the big reasons that attract people to minerals.

6. Generally speaking, color is not a good property to be used in the identification of minerals. It is usually the first property to confuse a novice collector into making an incorrect identification.
Many minerals have different colors and some minerals' colors are identical to other minerals' colors.
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7. Mineral Property Streak
Streak is closely related to color, but is a different property because the color of the mineral may be different than the color of the streak.
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8. Streak is actually the color of the powder of a mineral.
It is called streak because the proper way to test for streak is to rub a mineral across a tile of white unglazed porcelain and to examine the color of the "streak" left behind.
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9. Streak
Pyrite (known as "Fool's Gold") is always brassy yellow when found in crystals, even broken crystals, of any size; but when powdered, produces a black streak.
Gold's streak, by the way, is yellow!
Hematite's streak is blood- red
Galena's streak is lead gray
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10. Mineral Property # 2 Luster
A mineral’s luster is the way in which light reflects from the surface.
The two major types of luster are metallic & nonmetallic.
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11. Some other ways to describe luster are
Dull - just a non-reflective surface of any kind
Earthy - the look of dirt or dried mud
Fibrous - the look of fibers
Greasy - the look of grease
Metallic - the look of metals
Pearly - the look of a pearl
Silky - the look of silk, similar to fibrous but more compact
Waxy - the look of wax

12. What is the first thing someone notices about a mineral?
Quick Check
What is the first thing someone notices about a mineral?
What do we call the color of the powdered mineral?
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13. Hardness A mineral’s hardness is its resistance to being scratched.
A scale known as the Moh’s scale is often use
The classic scale for hardness was published in 1822 by Frederick Mohs, an Austrian mineralogist who got the basic concept from scratch tests performed routinely by miners.
The scale selects 10 minerals as standards, arranging in order of increasing hardness.
Baker 7th grade science

14. The classic scale for hardness was published in 1822 by Frederick Mohs, an Austrian mineralogist who got the basic concept from scratch tests performed routinely by miners.
The scale selects 10 minerals as standards, arranging in order of increasing hardness.

15. Mohs Scale
Baker 7th grade science

16. Brain Check 2 major types of Luster are…… Use the Mohs hardness Scale.
Name three things you can scratch Calcite with.
Baker 7th grade science