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Wildcat Mountain and Mt Washington. Kyle Migliorini. Rock Candy. 1 Glass jar or drinking ... Tie a short piece of cotton string to the middle of the pencil or stick. ...

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Snake River, ID

Hannah O’Brien



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Rock Candy

1 Glass jar or drinking glass 1 Food coloring (optional)

1 Piece of cotton string 1 c Water

1 Pencil or stick 2 c Sugar

1 Paper clip Additional sugar

Tie a short piece of cotton string to the middle of the pencil or stick. Attach a paper clip to the end of the

string for a weight.

Moisten the string very lightly, and roll in a bit of sugar (this will "attract" the sugar crystals from the

syrup to the string).

Place the pencil or stick over the top of the glass or jar with the string hanging down inside.

Heat the water to boiling, and dissolve the 2 cups of sugar into it.

For the biggest crystals FAST, heat the sugar-water solution a SECOND time, and dissolve as much

additional sugar as you can into it. Add a few drops of food coloring to the solution if desired.

Pour the solution into the prepared glass or jar and leave undisturbed for a couple of days.

Depending on how much sugar you were able to dissolve into the water, you should start to see crystals

growing in a few hours to a few days.

Source: Karen Mintzias

Just Recipes: http://www.melborponsti.com/index.htm


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IGNEOUS COMPOSITIONS

IGNEOUS PROCESSES AND IGNEOUS ROCKS

ULTRAMAFIC ROCKS

MAFIC derived from Magnesium and Ferrum (iron).

Dominated by Fe-Mg silicates, olivine and pyroxene.

Contains very little silica < 40%.

No feldspars or quartz.

Form deep in the Earth’s surface.

Very dark in color and dense.

Found at converging continental

plate boundaries.

PERIDOTITE OR DUNITE


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IGNEOUS COMPOSITIONS

IGNEOUS PROCESSES AND IGNEOUS ROCKS

MAFIC ROCKS

Silica content is 45-55%.

Contains dark plagioclase

feldspars, pyroxenes and

possibly olivine.

GABBRO - phaneritic

BASALT - aphanitic

SCORIA - aphanitic and

porous (vesicular).

BASALT is major constituent in

oceanic crust.


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IGNEOUS COMPOSITIONS

IGNEOUS PROCESSES AND IGNEOUS ROCKS

INTERMEDIATE ROCKS

Silica content is 55-65%.

Contains dark plagioclase

feldspars, pyroxenes,

biotite and hornblende.

Very little if any quartz.

Lighter color than mafic rocks.

ANDESITE - aphanitic

2nd most abundant volcanic

rock in Earth’s crust.

DIORITE - phaneritic


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IGNEOUS COMPOSITIONS

IGNEOUS PROCESSES AND IGNEOUS ROCKS

FELSIC ROCKS

Felsic comes from Feldspar and Silica.

Silica content is >65%.

Rich in orthoclase, muscovite

and quartz.

Lighter color than intermediate

rocks.

Wide variety in texture in felsic rocks.



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APHANITIC TEXTURE

RHYOLITE

FELSITE


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GLASSY TEXTURE

OBSIDIAN

Forms when gas-poor felsic

lava cools very quickly.

PUMICE

Forms when gas-rich felsic lava

cools very quickly.


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IGNEOUS ROCK CLASSIFICATION

IGNEOUS PROCESSES AND IGNEOUS ROCKS

COMPOSITION

PHANERITIC

APHANITIC

GLASSY


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CREATION OF MAGMA

IGNEOUS PROCESSES AND IGNEOUS ROCKS

Rocks are generally composed of several minerals.

Consequently, rocks don’t just simply melt.

Different minerals melt at different temperatures.

Rocks undergo PARTIAL MELTING.

Some of the rock stays solid.

Generally those minerals with high melting point

are last to melt.

Those with lower melting points become liquid first.

HEAT, PRESSURE and WATER CONTENT all affect the

melting of rocks.


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CREATION OF MAGMA

IGNEOUS PROCESSES AND IGNEOUS ROCKS

HEAT

Comes from:

Radioactive Decay

Heat produced from Earth’s formation still

rising to be released.

Frictional heat from plate movement.

Temperature rises with depth in the Earth

THERMAL GRADIENT.

Increased temperature causes minerals to melt.


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CREATION OF MAGMA

IGNEOUS PROCESSES AND IGNEOUS ROCKS

PRESSURE

High pressure on rocks acts to make the bonds stronger.

Pressure increases -- melting point increases.

If pressure is released quickly, melting will occur.


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CREATION OF MAGMA

IGNEOUS PROCESSES AND IGNEOUS ROCKS

WATER CONTENT

Water, even in small amounts lowers melting point.

Due to polarity of water molecules.

Decreased pressure and water content greatly lowers

melting point.

Increases bond breaking ability of water.

In subduction zones, wet oceanic crust is pushed down

with increasing pressure causing increased

melting.


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