1 / 30

Important Non-Silicates

Important Non-Silicates. Hematite-Corundum. Ilmenite FeTiO 3 is similar. Halite and Galena. Pyrite. Diamond. Diamond. Sphalerite. Chalcopyrite. Halite and Calcite. Calcite. Fluorite. Uraninite UO 2 is isostructural. Goethite. Goethite. Goethite. Lepidocrocite. Lepidocrocite.

cliff
Télécharger la présentation

Important Non-Silicates

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. Important Non-Silicates

  2. Hematite-Corundum • Ilmenite FeTiO3 is similar

  3. Halite and Galena

  4. Pyrite

  5. Diamond

  6. Diamond

  7. Sphalerite

  8. Chalcopyrite

  9. Halite and Calcite

  10. Calcite

  11. Fluorite • Uraninite UO2 is isostructural

  12. Goethite

  13. Goethite

  14. Goethite

  15. Lepidocrocite

  16. Lepidocrocite

  17. Bauxite and Limonite

  18. Perovskite

  19. Perovskite in the Mantle • Perovskite is CaTiO3 • Enstatite (Mg Pyroxene) = MgSiO3 • Can collapse to perovskite structure at high pressure

  20. Rutile

  21. Rutile

  22. Rutile • Cassiterite SnO2 is isostructural

  23. The Spinels • AB2O4 • A is divalent, B is trivalent • Oxygens in cubic close-packed structure • In a close-packed structure, there is one octahedral site for every oxygen and two tetrahedral • Ideally B occupies half of octahedral sites and A occupies 1/8 of tetrahedral sites

  24. Normal and Inverse Spinels • In normal spinels, B (trivalent) occupies octahedral sites and A (divalent) occupies tetrahedral sites • In inverse spinels, A (divalent) occupies octahedral sites and B (trivalent) occupies tetrahedral sites • In real spinels there is a lot of crossover

  25. Important Spinels • Spinel (normal) MgAl2O4 • Hercynite (normal) FeAl2O4 • Magnetite (inverse) Fe++Fe+++2O4 • Chromite (inverse) FeCr2O4 • Ulvospinel (inverse) Fe2TiO4 • Franklinite (inverse) ZnFe+++2O4 • Maghemite (inverse) Fe2O3

  26. Spinel

  27. Spinel

  28. Spinel

  29. Spinel

  30. Spinel in the Mantle • Spinel = AB2O4 • Forsterite (Mg olivine) = Mg2SiO4 • Can collapse to SiMg2O4 at high pressure • Si in octahedral sites, not tetrahedral!

More Related