•***A mineral is a naturally occurring, inorganic,
solid with a crystalline structure and a consistent
The 5 Characteristics of a Mineral
•Naturally occurring - can’t be man made (no
synthetics such as cubic zirconium)
•Inorganic - not made from living organisms
•Solid - No molten rock
5 Characteristics Continued…
•Crystal Structure - elements arrange in a regular
and predictable pattern.
•Chemical composition - minor variations allowed
of a diamond
Fundamental Atomic Theory
• Elements cannot be broken down by chemical
• Atoms are the basic component of an element.
• Atoms are composed of a nucleus containing
protons and neutrons, with an electron cloud
Fundamental Atomic Theory cont...
• Ions: Atoms that have lost or gained an electron and
are now charged.
• Cation: Lost an electron, positive (+) charge.
• Anion: Gained an electron, negative (-) charge.
• Minerals form by combinations of atoms and ions
held together by bonds.
Halite - rock salt
• Physical Properties: Run tests on the
physical characteristics of the sample.
• Crystal Structure: Shape of the sample.
• Chemical Properties: Reaction to acid,
taste, or smell.
Studded IPod Shuffle.
• Luster: How the mineral reflects light.
• Is it Metallic (M), or Nonmetallic (NM)?
Physical Properties cont.
• Hardness: Resistance to
• Moh’s Hardness Scale
• 1 - softest mineral (talc)
• 10 - hardest mineral (diamond)
• Fingernail - 2.5
• Penny - 3.5
• Glass - 5.5
• Steel Nail - 5.5
• Streak plate - 6.5
• Does the mineral break along flat surfaces?
No - uneven breakage,
Fracture (F) Yes - mineral splits along
parallel planes, Cleavage ( C )
Phys. Properties Cont.
• Streak: Color in powdered form.
– Scrape the sample across the streak plate, what
color is left behind?
• Specific Gravity (density): Weight of the
mineral compared to an equal volume of
• Color: LEAST RELIABLE physical
• The arrangement of ions in the atomic
structure determines the crystal shape.
Ex. Corundum Ex.
Ex. Pyrite Hematite Ex. Zircon
Crystal Shape cont.
Orthorhombic Monoclinic Triclinic
Ex. Topaz Ex. Kunzite Ex. Amazonite
• Reaction to acid
• Refracts Light
• Silicates are the largest group
• Make up 95% of the Earth’s
• Contain silicon and oxygen.
• Silicon - Oxygen tetrahedron,
– Each Si is surrounded by 4
– Strong bonds, high hardness.
Important silicate minerals
• Feldspars: 50% of Earth’s crust
• Quartz: Abundant in Continental crust
• Pyroxenes and Amphiboles
• Olivine: Rare in Continental crust
Mined for metals or
Gems: Used for