Identification of Minerals is a topic in Earth Science SHS.

1. ANNYROSE ALEJAGA-JAVIER,TII

2. WHAT IS MINERALS?
•Minerals are naturally occurring,
inorganic solids with definite Chemical
composition and a Crystal Lattice
structure.
•Minerals can be identified by their
physical characteristics which are
related to their chemical composition
and bonding.

3. WHAT IS MINERALS?
ØCrystal Lattice – is the geometry of how
the atoms are arranged and bonded
together.
ØChemical formula – are the types and
proportions of the chemical elements.

4. HOW ARE MINERALS IDENTIFIED?
•Mineralogist are scientists who study
minerals and although they might using
high-powered microscopes to identify
minerals, but most are recognizable using
physical properties such as; Color, Streak,
Luster, Specific Gravity, Hardness,
Cleavage, Fracture, Tenacity, and Crystal
Shape.

5. COLOR
• Some minerals come
in many different
colours. Quartz for
example may be clear,
white, grey, brown,
yellow, pink, red, or
orange.

6. COLOR
• Color can help but do
not rely on color as the
determining property.
For example, a quartz
having a tiny amount
of iron can appear
purple.

7. STREAK
• Refers to the color of a
mineral’s powder and it is
a more reliable property
than Color because
streak does not vary.
• Minerals of the same
color may have a
different colored streak.

8. SPECIFIC GRAVITY
• Refers to the density of the
substance / mineral.
• It is also refers to the mass of
the mineral compared to the
mass of an equal volume.
• Even though the two different
minerals may have the same
volume, their density will vary.

9. HARDNESS
•It is the strength with which a mineral resist its
surface being scraped and punctured.
•It doesn’t refer to the mineral being difficult or
easy to break.
•Mineral hardness can’t be specified without a
specialized tools, it can only be specified with
the use of Mohs Scale.

10. MOHS HARDNESS SCALE
HARDNESS INDEX MINERALS COMMON OBJECTS
SOFTER
1. Talc
2. Gypsum 2.5 – fingernail
3. Calcite 3.5 – pure, untarnished copper
HARDER
4. Fluorite
5. Feldspar 5 to 5.5 – stainless steel
5.5 to 6 – glass
6. Apatite 6 to 6.5 – hard steel file
HARDEST
7. Quartz
8. Topaz
9. Corundum
10. Diamond

11. CLEAVAGE
• Breaking a mineral also break
its chemical bonds and since
bonds are weaker than the
other bonds, each type of
mineral is likely to break
between weaker atomic
bonds.
• Cleavage is the tendency of a
mineral to break along certain
planes to make a smooth
surfaces.

12. FRACTURE
• It is a break in a mineral that is
not along a cleavage plane
and unlike a cleavage, a
fracture is not always the same
between minerals.
• A fracture may be Conchoidal,
which is similar when a thick
piece of glass breaks, or
Irregular, which does not show
any of the qualities of other
fracture types.

13. TENACITY
• Refers to the behaviour of
the mineral under
deformation or stress such
as; cutting, crushing,
bending or hitting.
• Simply defined as the
reaction of the mineral
towards forced change.

14. CRYSTAL SHAPE
• All minerals are crystalline but
only some have the
opportunity to exhibit the
shapes of their crystal forms.
• If a mineral has a space while
it grows it may forms natural
crystal, with a crystal shape
following the geometry of the
Mineral’s Crystal Lattice.

15. CHEMICAL PROPERTIES OF
MINERALS
•Aside from their physical characteristics,
minerals can also be identified through their
chemical properties.
•All minerals have a certain chemical structure.
•The Solubility and the Melting Point of the
minerals can be utilized to described a mineral.

16. SOLUBILITY
•The ability of a substance to dissolve in a
solvent at a specified temperature.
•The solubility of a mineral can expose the said
mineral’s chemical structure and components
that comprises the mineral.

17. MELTING POINT
•The specific temperature wherein a solid
substance is converted to a liquid.
•Minerals with highly compact atomic bonds
have a high melting point.
•This is also instrumental towards the study of
minerals as it provides additional data in
regards to the mineral’s properties and
characteristics.

18. LUSTER
•Is the the relative differences in the
opacity and transparency of a mineral as
light is reflected on its surface. This
describes the ‘sparkles’ of the mineral
surffaces.