Physical properties of minerals such as luster, cleavage, color, streak, hardness, fracture, transparency, magnetism, and tenacity.

1. Physical Properties
of Minerals
Prepared by: Jerome A. Bigael, Leyte Progressive High School

2. To classify a mineral resource, the minerals in
the rock should first be identified. Minerals can
be identified through their physical properties.
In some cases, some minerals may be found
in different places and in different forms but
their fundamental physical properties remain
the same.

3. 1.Color
•The most evident characteristic of and is
usually the first property used to identify
minerals. It is a result of the way minerals
absorb light.
•When a mineral absorbs all the color of
spectrum except that of a certain color,
the mineral will appear in that color

4. •However, this property may not be
used in identifying translucent to
transparent minerals due to the
presence of other trace minerals or
impurities.

5. Mineral Mineral Color
Augite Brown, green ,black ,purple
Biotite Black, brown, green
Calcite Pearlescent and pale colors
Dolomite Colorless, pink, pale brown
Feldspar Yellow, white, pink, green,
gray
Hematite Metallic gray or black
Hornblende Green, yellow, brown, black
Limonite Black, brown, yellow
Sulphur Pale gold

6. Augite = Brown, green ,black ,purple

7. Biotite = Black, brown, green

8. Calcite = Pearlescent and pale colors

9. Dolomite = Colorless, pink, pale brown

10. Feldspar = Yellow, white, pink, green, gray

11. Hematite = Metallic gray or black

12. Hornblende = Green, yellow, brown, black

13. Limonite = Black, brown, yellow

14. Sulphur = Pale gold

15. 2.Streak
•The color of mineral in powder form.
•Usually the mineral is rubbed on a
streak plate to determine its color.

17. 3.Hardness
•The measure of the mineral’s
resistance to scratching.
•To quantify the hardness of a
mineral, the Mohs Scale is used.
•The harder the mineral, the less
prone to scratches.

18. Mohs Relative
Hardness
Mineral Common Objects
1 Talc powder
2 Gypsum fingernails
3 Calcite tooth
4 Fluorite Iron nail
5 Apatite Window glass
6 Feldspar Steel file
7 Quartz porcelain
8 Topaz Hardened steel
9 Corundum Sapphire and ruby
10 Diamond none

19. 4.Cleavage and Fracture
•Cleavage and fracture are used to
describe how minerals break into
pieces.

21. 5.Crystalline
structure/crystal lattice
•The periodic array of atoms
•This is a unique arrangement of atoms in a
crystal.
•A hand lens is used for checking the
crystalline structure.
•Non crystalline structure minerals are called
“amorphous”; special lenses are needed to
validate this.

22. 6.Transparency/Diaphaneity
•Indicate the extent of
light that can pass
through the mineral.
•The degree of
transparency may
depend on the
thickness of mineral.

23. 7.Magnetism
•Indicates the
ability of the
mineral to
attract or repel
other materials.

24. 8.Tenacity
•the mineral’s ability to hold its
particles together or the mineral’s
level of resistance to stress such as
bending, breaking, crushing, or
tearing.
•It indicate if the material is brittle,
elastic, malleable, etc.

25. 9.Luster
•Shows how much light is reflected in
a mineral.
•This depends on the brilliance of
light used to observe the surface of
the mineral.

26. Classifications of Luster:
•Metallic, mineral is opaque and behaves like
metal when reflecting light.
•Submetallic, mineral is opaque, dull, and
dark colored.
•Nonmetallic, mineral does not reflect light
like a metal.
•Waxy, mineral looks like paraffin.
•Vitreous, mineral looks like a broken glass.

27. 10.Odor
•The distinct smell of a mineral that is usually
released from a chemical reaction manifested
when the mineral is subjected to water, heat,
air and friction.
•Sulfur, for example smells like what is emitted
when lighting a match.
•The strength of this smell increases when
heated or stuck, giving off an odor similar to
rotten eggs.

28. 11.Specific Gravity
•It is the measure of the density of the
mineral.
•It determines how heavy the mineral is
by its weight to water.
•Specific gravity is used especially when
two minerals have the same size and
color.

29. Other Properties:
•Taste – some minerals have a
characteristic taste.
For example Halite tastes like
salt.

30. Acid Reaction
•Some minerals that contain
carbonate (CO3) will react with
diluted hydrochloric acid (HCl),
forming carbon dioxide(CO2) gas
bubbles.
•Calcite (CaCO3) will react with HCl

31. Feel
•Some minerals such as talc, feel
soapy or greasy.

32. Presence of Striations
•Some minerals, such as pyrite, have
closely spaced fine grooves on their
crystal faces.
• the state of being marked with
stripes or lines.