Mineral Properties

1
Mineral Properties
1) The type of elements present
2) The arrangement of atoms
3) The strength of bonding
Reference Tarbuck and Lutgens Pages 21 - 24
2
Mineral Properties
1) Specific Gravity
2) Hardness
3) Cleavage
4) Streak
5) Luster
6) Color
3
Specific Gravity
To determine specific gravity you need to carry
out the following three steps
4
Specific Gravity
To determine specific gravity you need to carry
out the following three steps
weigh the specimen submerged in water and record
the weight.
2)
5
Specific Gravity
To determine specific gravity you need to carry
out the following three steps
Specific Gravity weight in air
.
weight in air -
weight in water
6
Specific Gravity Density
Note (In Reference to Core Lab 4) Because
pure water at 4EC has a density of 1 g/cm3, the
specific gravity is equal to its density.
Thus Specific gravity Density.
2) Find the volume of the mineral sample.
3) Calculate density (which equals specific
gravity).
Density Mass(mineral)
Volume(mineral)
Specific Gravity
7
Specific Gravity
Given 1mL 1cm3 1g, we know the weight of an
equal volume of water in grams. We can then use
the following formula to calculate Specific
Gravity
8
Other Properties
These physical properties can be helpful to
identify minerals that are similar
9
Other Properties
These physical properties can be helpful to
identify minerals that are similar
10
Sample Problem
Explain how the specific gravity of a mineral is
determined.
Answer Specific gravity compares weight of
mineral to weight of equal volume of H2O. (i)
find the mass of the mineral using a scale or
balance. (ii) find the
volume of the mineral water displacement method.
(iii) find the weight of mineral in
water by suspending mineral . from
spring scale and weighing it immersed in water.
(iv) use the
formula S.G. density m/v or

S.G. weight of mineral in air
(weight in air) - (weight in H2O)