1. What is a mineral? "A mineral is a naturally occurring, homogeneous, inorganic, crystalline solid with an orderly internal structure and definable chemical composition"

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4. Types of bonds: Ionic bond - exchanged electrons - example Na+ and Cl- = halite, table salt. Fairly strong bonds and ionic bonds are the dominant type of bond in minerals Covalent bond - sharing of electrons between ions that do not readily gain or lose electrons. Example = diamond, all carbon in very strong covalent bonds in all directions. Most mineral bonds are combinations of covalent and ionic. 


5. Bonds between elements form a 3-dimensional array.
If a mineral is allowed to grow without running into anything, a crystal will form with flat (planar) surfaces, representing manifestations of the internal order.
Most of the time, however, minerals run into other minerals that are crystallizing at the same time, and the crystal faces do not develop.

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7. glass
Crystalline solid

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10. Factors that affect the arrangement of elements in a mineral are the sizes of the ions involved. If it is a mineral composed of just one element (copper, gold, graphite, diamond) [or if all ions are similar in size] then the ions all fit together very nicely.

12. Graphite or diamond? polymorphs

13. If there are two or more elements in the mineral formula of different size, then the arrangement of the ions will be very different. Example: quartz, SiO2 made of silica tetrahedra (but all oxygens are shared, so formula is SiO2) - 4 large oxygen ions surround a very small silicon ion. Or NaCl

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