3. Characteristics & Properties of Minerals.pptx

(1st quarter) characteristics & Properties of minerals for grade 11

1. MINERALS

2. Minerals make up the rocks beneath your feet, the soil that supports plants, and the deep rock of Earth’s mantle.

3. Minerals are naturally occurring, solid, inorganic substances. They have a regular, repeating arrangement of atoms and molecules. The study of minerals is known as mineralogy . People who study minerals are called mineralogists .

4. What are Minerals ? Minerals are the building blocks of rocks. Mineralogists use the criteria to determine whether a material is classified as a mineral or not.

5. Characteristics of Minerals: 1 . naturally occurring- term which identifies mineral as part of earth’s natural processes. 2 . inorganic - means a substance is not a product of an organism. 3. homogeneous solid - minerals should have definite volume and rigid shape 4. definite chemical composition —represented by a chemical formula 5. orderly crystalline structure - atoms of minerals are arranged in an orderly and repeating pattern

6. PROPERTIES of a MINERAL

7. Crystalline in Structure / Habit Habit is the term mineralogists use when referring to the crystal structure and shape of a mineral. Some minerals have distinctive shapes. For example, some are shaped like cubes. Others may be shaped like prisms or pyramids.

8. Colour The most obvious property of a mineral, its color, is unfortunately also the least diagnostic. In the same way that a headache is a symptom for a whole host of problems from the flu to a head injury, many minerals share the same color.

9. Colour Part of the reason that the color of minerals is not uniquely diagnostic is that there are several components of the crystal compositions and structure that can produce color. The presence of some elements, such as iron, always results in a colored mineral, but iron can produce a wide variety of colors depending on its state of oxidation – black, red, or green, most commonly .

10. Lustre (or Luster ) This refers to the way light reacts with a mineral. Minerologists use adjectives like metallic, nonmetallic, dull, greasy, pearly and waxy to describe luster. For example pyrite has a metallic lustre . Gypsum has a pearly lustre and talc has a dull lustre .

11. Hardness The hardness of minerals is measured using the Mohs scale of mineral hardness . To test the hardness of a mineral, the mineral is scratched using different objects. The tougher the object, the harder the mineral .

12. Did you know? The Mohs scale (pronounced MOZE) was introduced in 1822. It originated when Friedrich Mohs chose ten minerals and assigned numbers to them based on the relative ease or difficulty in which stone can be scratched by another.

13. Diaphaneity / Transparency This refers to how see-through a mineral is / ability to allow light to pass . Some minerals are transparent . This includes minerals like quartz. Some minerals are translucent . These minerals let some light pass through, but not detailed shapes. Others are opaque . This means you cannot see through them at all.

14. Cleavage This refers to how a mineral breaks . If a mineral breaks along a flat surface or a geometric shape, then the mineral has cleavage. The mineral on the right has cleavage in many different directions.

15. Tenacity- describes the minerals reaction to stress. Brittleness - a mineral turns into powder Malleability - a mineral can be flattened by pounding with a hammer. Ductility - a mineral can be stretched into wire. Flexible but inelastic - Minerals are bent but they remain in the new position . Flexible and elastic- Minerals are bent, and they bring back to their original position.

16. Streak - color of mineral in powdered form.

17. Sectility - ability of minerals to be sliced by a knife .