1 / 25

Properties of Minerals

Properties of Minerals. Geologists use characteristics to tell one mineral from another. What is a Mineral?. Must be a solid. Must occur in nature. Must have a definable chemical composition ( NaCl ). Must have a crystalline structure. Must be inorganic.

lobo
Télécharger la présentation

Properties of Minerals

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Properties of Minerals Geologists use characteristics to tell one mineral from another

  2. What is a Mineral? • Must be a solid. • Must occur in nature. • Must have a definable chemical composition (NaCl). • Must have a crystalline structure. • Must be inorganic. • Video: http://www.youtube.com/watch?v=rTXSwnkieZc

  3. Mineral Properties we will mainly study: Luster Hardness Cleavage Streak

  4. Special Properties • Fluorescence • Optical Properties: double refraction • Taste • Conductivity • Reaction to Acid • Magnetism • Density • Video: http://www.youtube.com/watch?v=cjA2-MrWAVU • Song: http://www.youtube.com/watch?v=Sv_ApO7xiv8

  5. Luster • Refers to the way light reflects from the surface of the mineral. • There are two types of luster, • Metallic: looks like polished metal. • Nonmetallic: does not look like polished metal. • Nonmetallic can be shiny or dull.

  6. Pyrite has metallic luster

  7. Quartz has nonmetallic luster

  8. Hardness • Is measured by how easy it is to scratch. • Geologists use Mohs Hardness Scale

  9. Gypsum is soft, it can be scratched by a fingernail.

  10. Calcite is soft, but a little harder because it cannot be scratched by a fingernail, but it can be scratched by a penny.

  11. Fluorite is harder. It can be scratched by a nail, but not a penny or fingernail.

  12. Diamonds are the hardest mineral, so it scratches every mineral.

  13. Cleavage • Not all minerals have cleavage. • Some minerals split easily along a flat surface. • The number of lines that are created when a mineral is split will be the number of cleavage lines.

  14. Mica has cleavage in one direction. It breaks along one line.

  15. Feldspar has two lines of cleavage. It breaks along two lines.

  16. Streak • Red chalk on a chalk board makes red marks. White chalk makes white marks. • Not all minerals work this way. When some minerals are scratched along a ceramic streak plate, it creates a different color.

  17. Gold • When gold is run across a streak plate it makes a yellowish-gold color. • That makes sense.

  18. Pyrite or “Fool’s Gold” • When pyrite is run across a streak plate, it has a black or dark green streak. • Pyrite is not worth much money, while gold is worth a lot. They look alike, so miners call it fool’s gold.

  19. Hematite • Hematite’s color is grey, but its streak is red. • Hema means blood. • The mineral was named hematite because it looked like it was bleeding when it was taken across a streak plate.

  20. One mineral property we will not use… COLOR

  21. A mineral can be many different colors. Below is Mica.

  22. Many minerals can be the same color. Below are gold colored minerals. Which one is gold?

  23. The answer… None of them were real gold.

  24. Just like with people… Outside color does not tell you much about the important characteristics.

  25. Videos: Mineral Identification http://www.youtube.com/watch?v=VnM8ebB06MU Hardness Scale http://www.youtube.com/watch?v=7piTh8mH9zw

More Related