exam 2 - What is a mineral Naturally occurring Solid Formed...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
What is a mineral? Naturally occurring Solid Formed geologically Crystalline structure Definite chemical composition Mostly inorganic What is inside a crystal? The nature of atomic bonds controls characteristics Diamond and graphite are carbon polymorphs Diamond – strong covalent bonds: hardest mineral Polymorph same composition diff. structure Mineral formation Mineral growth is often restricted by lack of space Anhedral – grown in tight space no crystal faces Euhedral – grown in an open cavity, good crystal faces Anhedral are much more prevalent Euhedral crystals grow into the open space Physical Color Streak Luster Hardness Specific gravity Crystal habit Fracture or cleavage (know difference; fracture is a break and cleavage is a split) Same structure but different mineral Hardness Not linear it’s a logarithmic scale Scratching resistance of a mineral Derives from the strength of atomic bonds Cleavage Tendency to break along planes of weaker atomic bonds Cleavage produces flat, shiny surfaces Described by the number of planes and their angle Cleavage will break on weaker planes but on crystal face it just shatters when hit Silicate minerals
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Silicates are known as the rock-forming minerals They dominate Earth’s crust and mantle Independent tetrahedral (share no oxygens, are linked by cations) Single chains (silica link share two oxygens) Double chains (share two and three oxygens) Sheet silica (share three oxygens, flat sheets of linked tetrahedral, characterized by one direction of perfect cleavage) Framework silica (all four oxygens in each silica are shared, 3D) Minerals bond on oxygen, know different structures and what silica does Rocks Melted rock can cool above or below ground Extrusive igneous rocks- cool quickly at the surface Lava flows- streams or mounds of cooled melt Pyroclastic debris – cooled fragments Volcanic ash – fine particles of volcanic glass Volcanic rock – fragmented by eruption
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern