Download Minerals Are - Net Start Class

Minerals Are:
* Solid, inorganic
materials that form
naturally on or beneath
the Earth’s surface.
•Have a definite chemical
composition.
•Usually solid. High temp.
inside the Earth can melt
them.
•Naturally Occurring –
not man-made. Formed
as a result of
processes in the
natural world.
•Inorganic – not made
from things that were
once alive.
•Have definite crystal
structure – repeating
patterns of a mineral’s
atoms.
•Definite Chemical
Composition –
Each type of mineral has
the same proportions of
the same elements.
How Mineral Form
• Most minerals form when molten material
(magma) cools and hardens inside Earth
or on the surface
• Some form when a solution evaporates on
Earth’s surface
– Ex. Halite NaCl
How Minerals are Formed
• If magma or lava cool slowly then large
crystals will form
– Ex. Quartz
• If magma or lava cool quickly the small
crystals will form
– Ex. Feldspar
Identify Minerals
•Look at the Properties –
characteristics that
make the mineral
different from other
minerals.
Ways to Identify:
•Hardness
•Color
•Streak
•Luster
•Cleavage
•Density
Identifying Minerals
• Hardness- use Moh’s hardness scale p 95
of textbook
Color
• Not good to use.
• Several minerals come in
different colors.
Streak
• - color of the mineral’s powder found when
the mineral is rubbed on a piece of tile
Luster
• - how a mineral reflects light: glassy,
pearly, metallic, and earthy
Cleavage & Fracture
•Cleavage: split apart
easily along flat surfaces.
•Fracture: irregular
surface where it breaks
Cleavage
Fracture
Density
• Density = mass/volume
• Use a balance to find mass in grams
• Use a graduated cylinder to find volume in
milliliters
Other Properties:
• Chemical reaction: fizzes
with vinegar (Calcite)
• Transparent – can see
through it
• Opaque – pearly, cloudy
• Magnetic
* High Mass