Minerals
Note 3
- Over 4000 known minerals made up of elements
- Only 8 of these elements compose 98% of
continental crust
Oxygen
Silicon
Aluminum
Iron
Calcium
Sodium
Potassium
Magnesium
Atomic Structure A.Protons (p+) – positive particles in nucleus,
determines what element you have ( = to atomic #)
Atomic #
B. Neutrons - neutral particles
9
in nucleus,
(= to mass # minus atomic #)
C. Electrons (e-) – neg. particles
that orbit nucleus, neutral atoms
Flourine Mass #
have same # of e- as p+
18.998
D. Mass # - mass of protons
& neutrons
E. Ions - atom with more or less electrons than protons
F. Isotopes – varieties of same element w/ same # of
p+ but different # of neutrons
F
Use pg 614 (old), 646 (new) or pg 122 of
handbook) to complete the following practice
questions:
How many protons in:
Scandium ____
Osmium ____
Iron ____
Gold ____
How many electrons in:
Sodium ____
Potassium ____
Fluorine _____
Uranium _____
How many neutrons in:
Lithium _____
Arsenic______
Calcium ____
Rubidium _____
Additional Mineral Properties Useful for
Identification:
A. Specific Gravity
- Comparison of weight of a mineral to an equal
volume of water
* example: Galena has a specific gravity of 7.5
1 liter of water weighs ~ 1 kg
So how much would a 1 liter
container of galena weigh?
_________
B. Taste – some minerals [like halite (rock salt)]
have a distinct taste
C. Magnetism – minerals with a high iron content
(like magnetite) can be magnetic
D. Double refraction – when you look through
mineral, letters appear doubled
E. Reaction to acid – minerals that contain calcium
carbonate like chalk or marble fizz when you drop
acid on them
Example of double refraction