1 / 23

Mineral Formation

Discover the formation of minerals and crystals from magma to evaporation. Learn the criteria for defining minerals, identification methods, and crystal growth processes. Dive into the world of rocks and minerals!

reyesm
Download Presentation

Mineral Formation

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. In 2008, crystals up to 39 feet long were found in a cave in Mexico at a depth of 1000 feet. The cave is extremely hot, with air temperatures reaching 136 °F with 90 to 99 % humidity. The cave is relatively unexplored due to these conditions. Without proper protection, people can only endure about ten minutes of exposure at a time. See the suits Mineral Formation

  2. Scoria Gneiss Coal The Earth’s crust is made up of two things: • Minerals and Rocks Rocksare combinations of minerals Minerals are individual crystals of all the same stuff ***You should see lots of different minerals in every single rock

  3. What is a mineral? Main Concept: Minerals are the building blocks of rocks! There are five main criteria for something to be a mineral: a) It must be solid a) It must occur naturally (not man-made) b) It is made of non-living material (never alive) c) It has a definite chemical formula (NaCl=salt) d) It has a crystal structure (Precious?)

  4. Examples: ***Notice how each is one single type of crystal! • Amethyst Calcite Garnet • Galena Gold Pyrite

  5. From stuff dissolved in liquids (Evaporation & Hot Water) From Cooling molten material Where do minerals come from? • Mineral crystals can form in two main ways:

  6. Minerals & Crystals fromMagma & Lava “Extrusive” Cooling: Lava cools Fast (Short Time = Small Crystals) • Minerals form from hot magma as it cools inside the crust, or as lava cools on the surface. • When these liquids cool to a solid, they form crystals (minerals). • Size of the crystal depends on time it takes to freeze into a solid. “Intrusive” Cooling: Magma cools slowly (Long Time = Large Crystals)

  7. Minerals Crystal Size When the hot material cools fast, it has smaller crystal size. When it cools slowly, it has large crystals. Granite Rhyolite You can see individual crystals in Granite = cooled slowly You can’t see many individual crystals in Rhyolite = cooled very fast

  8. Minerals formed by Evaporation • Some minerals form when solutions/mixtures evaporate: • When water evaporates, it leaves behind the stuff that’s dissolved in it. • The longer it takes to evaporate, the larger the crystal. • i.e. salt & water – ocean, • Halite, Gypsum, Calcite. ***All the white stuff = salt mineral crystals that formed when the water of this lake evaporated. The mineral material was left behind

  9. These salt crystals formed from salt water because as the water evaporated, the salt wasn’t dissolved anymore. So the chemical energy in salt takes over and crystals form. Do you notice the characteristic cubic crystalline shapes?

  10. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Luster:Describes how light is reflected from a minerals surface.

  11. More non-metallic lusters: Brillant Glassy Silky

  12. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Streak: Is the color of the minerals powder when dragged across a surface.

  13. Performing the streak test: Drag the mineral across the piece of porcelain tile and look at the (inside) powdered form of the mineral

  14. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Crystal shape: Different minerals make different crystal shapes

  15. Crystal Systems: It time allows and space is available, minerals will grow and take on geometric shapes Note: we have very few that exhibit these shapes due to being broken pieces

  16. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Hardness: Hardness is determined by a “scratch test”.

  17. Hardness testing: The hardness of a mineral is a way of describing how easy or difficult it is to scratch it, ranked on a scale of one to ten(10 is the hardest). Alert: Always start with the softest tool and stop using the harder tools at the first sign of a scratch Scrape the tool once across and listen for and/or feel the resistance

  18. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Breakage Pattern: Minerals either cleave (flat sides) or fracture (rough edges)

  19. Breakage Pattern Minerals will break along lines of weakness (if any) and will assume one of several shapes. If the mineral breaks in smooth or flat ways it means the minerals cleaves. Here are three common appearances: cleavage Basal: cleaves in one direction into flat sheets Right angle: cleaves in two directions with two flat sides Cubic: cleaves in three directions into cubes

  20. Breakage Pattern (cont’d) Some minerals don’t have any lines of weakness and will break with irregular, rough, or sharp edges. This appearance is called fracture. fracture Hackly- irregular Concoidal-rounded Splintery-fibrous

  21. How do we identify Minerals? We use the different physical and chemical properties of the mineral to identify it from other different minerals Luster:Describes how light is reflected from a minerals surface. Streak: Is the color of the minerals powder when dragged across a surface. Crystal shape: Different minerals make different crystal shapes Hardness: Hardness is determined by a “scratch test”. Color: Every mineral has some natural color…ex: Gold, Blue, Clear… Breakage Pattern: Minerals either cleave (flat sides) or fracture (rough edges)

  22. Special Properties • Some minerals display strange properties. • These can include: • Magnetism, fluorescence, and reactivity Fizzing! These minerals glow in the dark. A black light brings it out! The minerals in this rock react with acid The particles of minerals of this rock act like magnets

More Related