chapter 3 section 1. a mineral is ◦ naturally occurring ◦ inorganic- it has no carbon in its...
Post on 18-Jan-2016
214 Views
Preview:
TRANSCRIPT
MineralsChapter 3 Section 1
A mineral is◦Naturally occurring◦Inorganic- it has no carbon in its chemical formula
◦Has a definite chemical composition◦Has an orderly arrangement of atoms
◦4000 different minerals
Mineral
Crystalline- means that the atoms are arranged in a pattern that keeps repeating over and over
Atom patterns
Solid in which the atoms are arranged in orderly, repeating patterns.
Six major shapes to crystals◦Cubic◦Hexagonal◦Tetragonal◦Orthorhombic◦Monoclinic◦Triclinic
Crystals
6 major shapes of minerals
1. From Magma2. From Solution
Crystals form in 2 ways
After magma is released from below Earth’s surface it begins to cool
As it cools, atoms lose heat and move together forming compounds.
These compounds arrange themselves in regular repeating patterns or crystals
If magma cools quickly, the crystals are large
If magma cools slowly, the crystals are small
Crystals from magma
Crystals also form from minerals dissolved in water
Water can evaporate leaving crystals behind like halite or salt crystals
If too much substance is dissolved in a water then it can precipitate out forming a crystal
Crystals from solution
Most of Earth’s surface is made up of 8 minerals Oxygen- 46.6% Silicon-27.7% Aluminum- 8.1 % Iron- 5.0 % Calcium-3.6% Sodium- 2.8 % Potassium- 2.6% Magnesium 2.1% Other 1.5%
Mineral Composition
Most of the common rock forming minerals contain silicon and oxygen
They are called the silicates They contain silicon, oxygen, and 1 or 2
more elements
Mineral composition cont.
top related