Minerals Building Blocks of Rocks Minerals Building Blocks of Rocks.
ROCKS AND MINERALS - EJC Training School AND MINERALS.pdfDIFFERENCES BETWEEN ROCKS AND MINERALS...
Transcript of ROCKS AND MINERALS - EJC Training School AND MINERALS.pdfDIFFERENCES BETWEEN ROCKS AND MINERALS...
DIFFERENCES BETWEEN ROCKS AND MINERALS
• MINERALS
• Solid formations that occur naturally in the earth
• Have a unique chemical composition
• Defined by its crystalline structure and shape
• ROCKS
• Solid combination of more than one mineral formation
• Can be composed of several minerals
• Can also contain organic remains and mineraloids
• Classified according to the process of its formation
TYPES OF ROCKS
• Igneous
• formed when molten lava solidifies after a volcanic eruption
and is known to be rich in the mineral granite.
• Sedimentary
• formed from deposits of pre-existing rocks, pieces of once-
living organisms or chemical precipitation.
• Metamorphic
• formed by the transformation of one rock type to another,
usually under great heat and pressure.
TYPES OF ROCKS
Igneous
Intrusive
Extrusive
Sedimentary
Clastic
Biologic
Chemical
Metamorphic
Foliated
Non-foliated
MOH’S SCALE OF HARDNESS
• Most common method used to rank minerals
according to hardness.
• Devised by German mineralogist Friedrich Moh in
1812.
• Moh’s hardness refers to a mineral’s ability to resist
abrasion or scratching.
• A mineral with a given hardness rating will scratch
other minerals of the same and lower hardness
ratings.
MOH’S HARDNESS SCALE
Hardness Mineral Description
1 Talc Fingernail scratches it easily.
2 Gypsum Fingernail scratches it.
3 Calcite Copper penny scratches it.
4 Fluorite Steel knife scratches it easily.
5 Apatite Steel knife scratches it.
6 Feldspar Steel knife does not scratch it easily, but scratches glass.
7 Quartz Hardest common mineral. It scratches steel and glass easily.
8 Topaz Harder than any common mineral.
9 Corundum It scratches Topaz.
10 Diamond It is the hardest of all minerals.
IDENTIFYING MINERALS
• Some of the characteristics used to identify minerals
are:
• Colour
• Luster
• Streak
• Cleavage
• Hardness
• Specific Gravity
• Texture
• Crystal
IDENTIFYING MINERALS – COLOUR
• Although commonly used to describe a mineral, it is
not a very good way of identifying a mineral.
• Some minerals are nearly always the same colour,
but many come in a variety of colours.
• Some minerals change colour when the surface is
exposed to moisture and air.
IDENTIFYING MINERALS – LUSTER
• This is the way a mineral reflects light.
Words used to describe luster Example of Mineral
Brilliant Diamond
Dull Kaolinite
Glassy Quartz
Greasy Nepheline
Metallic Pyrite
Pearly Gypsum
Silky Kernite
IDENTIFYING MINERALS – STREAK
• The colour of the powder a mineral produces when
it is dragged across a hard, rough surface.
• For example, pyrite is a brassy, yellow colour, but it
makes a greenish, black streak when rubbed across
a rough surface.
IDENTIFYING MINERALS – CLEAVAGE
• The tendency of minerals to break along definite
planes, creating smooth surfaces.
• For example:
• Galena cleaves into little cubes
• Mica cleaves into thin sheets
• Calcite cleaves into slanting bricks
• Feldspar breaks into little steps
• Quartz cleaves into irregular chunks.
IDENTIFYING MINERALS – SPECIFIC GRAVITY
• The relative weight of a mineral compared to an
equal volume of water. The specific gravity
determines the density of a mineral.
• Two different gems that are the same size can
weigh different amounts.
Specific Gravity Classification of Weight
Less than 3 Light
3 – 5 Average
At least 5 Heavy
IDENTIFYING MINERALS
• Texture
• The physical appearance or character of a rock, such as
grain size, shape and arrangement.
• Crystal
• A solid whose atoms, molecules or ions are packed in a
regularly ordered, repeating pattern. Snowflakes, diamonds,
and common salt are common examples of crystals.
COMMON MINERALS AND THEIR PROPERTIES
Name Colour Streak Luster Hardness Other Properties
Graphite Black Black Metallic 1 Crystals are rare
Mica Colourless White Pearly 2.5-3 Flakes into sheets
Halite Colourless White Glassy 2.5 Salty taste
Galena Gray Gray Metallic 2.5-3 Crystal Cubes
Calcite Colourless White Glassy 3 Crystalline
Magnetite Black Black Dull 5.5-6.5 Magnetic
Pyrite Golden Black Metallic 6-6.5 Looks like gold
Feldspar Various White Glassy 6-6.5 Two cleavages
Quartz Various White Glassy 7 Round fracture
Corundum Gray White Glassy 9 Crystalline
USES OF ROCKS AND MINERALS Rock Use Mineral Use
Basalt Road building
materials
Quartz Glass, electrical components
and optical lenses
Granite Buildings, monuments
and tombstones
Diamond Abrasives
Marble Buildings, tiles Sapphire,
Ruby
Lasers
Obsidian Knives Copper Building construction, electric
cables and wires, switches, alloys
Pumice Scouring, scrubbing
and polishing
materials
Feldspar Glass and ceramic industries,
soaps, cement, fertilizer
Slate Roofs, chalkboards Calcite Cements, mortars, production of
lime
Coal Fuel Graphite Pencil lead, lubricant
Limestone Cement, paper,
petrochemicals,
insecticide, glass
Gold Jewelry, arts, medicine,
currency, scientific and
electronic instruments
BIBLE INCIDENTS IN WHICH A ROCK WAS SIGNIFICANT
Incident Text
Ten Commandments Exodus 31:18
God commands Moses to strike a
rock to provide the Israelites with
water
Numbers 20:2-13
David kills Goliath with a stone 1 Samuel 17
Jesus orders that the stone
covering the tomb of Lazarus be
removed
John 11:38-44
Parable of wise and foolish builders Matthew 7:24-29
Stoning of Stephen Acts 6-7
Woman caught in adultery John 8:1-11
FOUNDATION STONES OF THE NEW JERASULEM
• These can be found in Revelation 21:19,20 and are listed below: • Jasper
• Sapphire
• Chalcedony
• Emerald
• Sardonyx
• Sardius
• Chrysolyte
• Beryl
• Topaz
• Chrysoprasus
• Jacinth
• Amethyst.
SOURCES
• http://en.wikibooks.org/wiki/Adventist_Youth_Honors_Answer_Book/Nature/Rocks_%26_Minerals
• http://www.differencebetween.net/science/difference-between-rocks-and-minerals/
• http://geomaps.wr.usgs.gov/parks/rxmin/rock2.html
• http://geology.com/rocks.shtml
• http://chemistry.about.com/od/geochemistry/a/mohsscale.htm
• http://library.thinkquest.org
• http://www.nma.org/publications/common_minerals.asp
• http://www.coaleducation.org/lessons/wim/20.htm
• http://www.rocksforkids.com/RFK/identification.html