 Naturally occuring  Solid  Formed by inorganic processes  Have a crystal structure  Definite chemical composition  To be a mineral – MUST HAVE ALL 5 characteristics

 Formed by natural processes  Quartz formed from magma that cools and hardens beneath Earth’s crust.

 Always have a definite shape and volume  Particles in a mineral are packed tightly together

 Particles line up in a pattern that repeats over and over again.  This repeating pattern forms a crystal.  Crystals have flat sides that are called faces.

 Minerals are formed from materials that were not part of a living thing

 Means mineral always contains certain elements in the same proportions.  Elements are made of a single atom.

 Most minerals are compounds – 2 or more elements combined in fixed proportions.  Gives minerals their distinct properties  Quartz – 1 silicon for every 2 oxygen  Elements such as copper, silver, and gold are minerals.

 Can be challenging  Each mineral has characteristic properties that are used to identify it.

 Color  NOT very reliable, a lot of minerals may have the same color

 Color of the mineral as a powder  Streak IS reliable – often times it is different from the color of the mineral

 How light is reflected from the mineral’s surface.  Examples: metallic, glassy, earthy, silky, waxy, and pearly

 Moh’s Hardness Scale – used to rank hardness (resistance to be scratched)  Diamond is the hardest naturally occurring mineral  Talc is the softest  

 Mass/volume!!!!  I heart density!  Every mineral has a specific density.

 Regular pattern in a mineral that repeats over and over again.  Can be used to identify small mineral samples  Different crystal shape example:  Cubic (halite)

 Minerals that split or peel easily along flat surfaces have cleavage.  Depends on how the atoms are arranged.  Minerals that do not split evenly have fracture. This describes how minerals look when they break in a certain way.  Quartz breaks into curved, shell like surfaces.

 Calcite bends light and produces double images when it is looked through.  Some conduct electricity  Some are magnetic  Some glow under UV light  Some have characteristic tastes