Transcript Rocks-and--Minerals-POWERPOINTx

Directions: Write the
Warm-up for Monday, 3/21/16 sentence and fill in the
Title your paper Warm-ups for 3/21 – 3/24/16
blank.
1. Below earth’s surface are areas of melted rock called ______.
When magma ______ and _______, ________ rocks form.
cooled quickly
cooled slowly
2. A ___________ rock is a rock
that is formed from other rocks by
extreme _______and ________.
.
3. _________ rocks are formed from
sediments that are __________ and
_________ together.
Warm-up for Monday, 3/21/16
Title your paper Warm-ups for 3/21 – 3/24/16
1. Below earth’s surface are areas of melted rock called magma.
When magma cools and hardens, igneous rocks form.
cooled quickly
cooled slowly
2. A metamorphic rock is a rock
that is formed from other rocks by
extreme heat and pressure.
.
3. Sedimentary rocks are formed
from sediments that are compacted
and cemented together.
What is a rock?
A rock is a naturally occurring solid substance that is
normally made of minerals.
Some rocks are made of only one mineral. Others are
made of several minerals combined.
By figuring out what minerals are in a rock and
understanding how they are formed geologists place
rocks into one of three groups:
Igneous
metamorphic and sedimentary .
Igneous Rocks
Below earth’s surface are areas of melted rock
called magma. When magma cools and hardens,
igneous rocks form.
Igneous rocks can also form from lava above earth’s crust.
The texture of an igneous rock depends on how fast the magma cools to
form the rock.
The slower it takes to cool the more mineral grains will form. If it cools
quickly, the rock will have a smoother, glassy texture.
obsidian
granite
basalt
Sedimentary
Rocks
These layers are made of tiny
pieces called sediments.
Some sediments are formed from
rocks or minerals.
Others are bits of plants, shells, or
other hard materials.
Sedimentary rocks are formed from sediments that are
pressed and cemented together.
It can take millions of years for sediments to become rocks!
metamorphic
Rocks
When rocks are under extreme heat or
pressure (like under earth’s surface!) their
physical appearance can change.
A metamorphic rock is a rock that is formed from other
rocks by extreme heat and pressure.
granite
gneiss
The Rock Cycle
What is a mineral?
Minerals are the building blocks of rocks.
Minerals must occur naturally and are non-living.
Minerals can be elements or compounds.
They are pure substances with a chemical formula.
Minerals have a crystalline structure.
Rocks are mixtures of minerals and other materials.
Scientists have discovered over 3,000 types of minerals!
A mineral is a natural, nonliving substance.
How do we identify minerals?
We observe the physical
properties of minerals.
Minerals are identified by their
physical properties:
• hardness
• crystal shape
(form)
• luster
• color
• streak
• cleavage/fracture
• density (specific
gravity)
• special properties
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reaction to acid
fluorescence
salty taste
magnetism
But don’t worry…we’re only going to
focus on FIVE!
• Hardness (scratch test)
• Luster
• Color
• Streak
• Density
Physical Properties of Minerals
Color: Color alone, cannot identify minerals. Many
minerals have the same color.
Quartz can be many different colors!
Hardness: refers to a minerals ability to scratch
another mineral or be scratched (scratch test). The
MOHS’ Scale shows the hardness of some common
minerals. Each mineral has a number one - ten. Ten is
the hardest kind.
Luster: refers to the way light bounces off the surface of a
mineral. Main categories are metallic (shiny luster) and
nonmetallic which can be described as dull, waxy, pearly,
glassy, and others.
Streak: If you scratch a mineral along a white tile,
it leaves behind a powder. A minerals streak is the
color of that powder. The streak may be different from
the color of a mineral’s surface! The color of the streak
is a minerals true color.
Properties of minerals
mineral
color
mica
feldspar hematite
pyrite
white, green, white, pink,
gold or
silver, or
gray, or
gray or brown
brassy yellow
brown
smoky black
luster
pearly
dull or glassy
metallic or
dull
streak
white
white
red
green-black
hardness
2 - 2.5
6-6.5
6-6.5
5-6
metallic