Rocks
You became an expert in one rock family:
- Igneous
- Intrusive
- Extrusive
- Foliated
- Nonfoliated
- Clastic
- Organic
- Chemical
- Geode, Sandstone, Shale, Limestone, Coal, Halite
- Gneiss, Marble, Slate, Quartzite, Schist
- Obsidian, Pumice, Granite, Basalt
Choose one of the rock types below. Tell as much as you can about it including
- What family it belongs to.
- What group within its family it belongs to.
- How it formed.
- What it looks like.
October 10th, 2006 at 8:33 am
Metamorphic rocks
Quartzite is a nonfoliated metamorphic rock.
crystals in nonfoliated rocks combine and change. they are nonfoliated because they are composed of mostly one mineral. Quartzite forms from Sandstone which is mostly the mineral quartz. it looks like a crystal, it doesn’t have different layers, just mostly looks like one color, and shinyy.
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October 10th, 2006 at 8:34 am
Geodes are chemical sedimentary rocks. They are rough and dark on the outside, but they are really cool looking on the inside. They taste pretty good too. Anyway, these rocks are formed when Water evaporates and leaves minerals behind.
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October 10th, 2006 at 8:35 am
I am going to tell you about Marble. Marble belongs to the metamorphic family. It is a non-foliated and nice looking rock. This rock is formed. They are formed deep inside the earth. Heat, and pressure from the rock above flatten and bend the rock or even exchange atoms, forming new minerals. And it is a smooth rock that does not have layers. And thats Marble.
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October 10th, 2006 at 8:36 am
Marble- Marble belongs to the metamorphic family under non foliated. Marble is formed by pressure and heat over the years. Marble as you may know of it is used for counter tops and tile on floors. Marble is very smooth and shiney along with it’s color such as black, light green, blue, and brown sometimes red.
HoW sMaRt Am I LoL
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October 10th, 2006 at 8:38 am
basalt is a dark colored, fine grained rock. it forms when hot magma cools in under the earths surface, which means it is an intrusive rock, since it is formed from cooling lava and under ground it would be classified as an intrusive igneous rock.
Jared – I think it’s really extrusive. It tends to form from undersea volcanoes. -Mr. Light
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October 10th, 2006 at 8:39 am
I am in the Sedimentary rock family and iI choosed coal. Coal is formed of millions and millions of old plants in the swamp. Coal is in the Organic part of the sedimentary rock.
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October 10th, 2006 at 8:39 am
okay heyy again. metamorphic rocks are made by heat and pressure molding and bending the rock.
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October 10th, 2006 at 8:39 am
Hayley I think you described Quartzite very well. What else has a role in makeing Qaurtzite?
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October 10th, 2006 at 8:40 am
intrusive
the igneous rocks that formed inside the earth are called intrusive and take granite that is formed in side the earth. If it has fine grains it will cool faster, If it has coarse grains it will cool much slower than fine grains.
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October 10th, 2006 at 8:40 am
I have the sedimentary rock family. I chose the rock limestone.
limestone is a sedimentary rock it is made from the mineral clcite. It is non-clastic. If yoou drop vinegar on limestone it will fizz. It is formed by sediments from the bottom of evaporated lakes and ponds. It is also formed from sea aniimal shells. Lime stone is a grayish blackish color. It is used for making concrete.
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October 10th, 2006 at 8:41 am
Coal belongs to the sedimentary family and organic group. Coal is formed by stuff falling and rotting in the acient times of the dinosaurs. Coal is black and leaves black makes if you were to scrape it across something.
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October 10th, 2006 at 8:41 am
just adding another thing it is formed by heat and perrsure underneath the surface of the earth.
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October 10th, 2006 at 8:42 am
Igneous rocks are seperated into two groups, intrusive and extrusive. Intrusive rocks are formed when magma cools under ground. Extrusive rocks are formed when lava (magma) cools after it has ereupted from a volcanoe. Some igneous rocks are Obsidian, Pumice, Granite, and Basalt. I am going to tell you about Pumice. Pumice is and Intrusive rock. It is the only intrusive rock in the little group I just named. Since it is intrusive, it means it is magma that has cooled under ground. This rock is amazing because it is the only rocks that can float. This is because it has air pockets all through the rock. When you look at this rock you should know it is Pumice because it is kinda rough and you can see little holes in the rock here and there. This rock is also extremely light. It can be used for decrative landscaping.
Alicia: Nice explanation. One thing, though. Pumice is a volcanic rock. It forms when lava shoots out of a volcano with air pockets. It isn’t intrusive. – Mr. Light
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October 10th, 2006 at 8:43 am
Metamorphic rocks are formed because the earths crust moves and changes other types of rocks into metamorphic. Slate is formed mostly from shale, it seperates easily and so its used to make roof tiles and floor tiles. Its smooth and sometimes rough.
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October 10th, 2006 at 8:47 am
Igneous Rocks:
Igneous rocks are formed above or underground. When igneous rocks form when melted rock (magma) deep in the earth get trapped in these small pockets, when the pockets cool the become igneous rocks.
Pumice rocks is a type of ingneous rocks its in the extrusive family. Pumice rock forms when granitic lava. Lava is alot lighter so it cools quicker. Pumice rock looks like small crystals.
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October 10th, 2006 at 8:52 am
1. Limesoin belongs to the sedimentary famley.
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October 10th, 2006 at 9:33 am
Igneous rocks form when magma cools.
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October 10th, 2006 at 9:35 am
Igneous rocks:
Basalt- The black beaches of Hawaii are formed from eroded basalt.
Pumice- Is used for decorating landscape stones.
Obsidian- Is used for decorating.
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October 10th, 2006 at 9:37 am
Sandstone is a sedimentary rock. It is part of the clastic subgroup, meaning it is formed from the little pieces of rocks that have broken off.
Sandstone is formed when particles of a different rock become compacted and then cement to each other. When the particles stick, that creates a sandstone rock.
The picture of sandstone, it was smooth, mostly a white-off white color and non-jagged edges.
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October 10th, 2006 at 9:37 am
Quartzite belongs in the Meaamorphic family. It’s formed by deep underneath the Earth when the Crust of the Earth moves, the tempature gets so hot that after years, and years, and years other metamorphic rocks forms into Quartzite. Quartzite is a big and heavy rock. Quartzite is non-foliatred because the rock doesn’t have layers.
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October 10th, 2006 at 9:38 am
Hey, I am going to tell you something about sedimentary rock. Chemical rocks are a sediment and it is formed when water is evaporated and minerals are left behind.
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October 10th, 2006 at 9:38 am
Igneous rock:
Obsidian is generaly black with some small white and grey swirls through out it. It is a smooth, glass like rock with lots of sharp angular edges. This rock is a intrusive rock, which means it cools slowly inside a volcano. An easy way to tell an intrusive rock from an extrusive rock is that extrusive rocks have air bubbles all over it becuase it forms out side of a volcano where it is exposed to air colder then the magma.
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October 10th, 2006 at 9:38 am
Basalt Is a type of extrusive, igneous rock and the uses for basalt is gravel and aggregate, Extrusive is unique by the molten rock cools down before it reaches the surface.
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October 10th, 2006 at 9:39 am
Igneous rocks are formed when a volcano’s lava either cools while inside the volcano or when the lava has come out and cooled. When the rock cools inside the volcano it is called instrusiveand when the rock cools outside the volcano it is called exstrusive. Some example of instrusive is …..
* Granite
*Obsiden
exstruvise is…
*Pumice
*Balsalt
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October 10th, 2006 at 9:40 am
Obsidian rocks are actully glass, they are transparent and are kinda browinish, Obsidian rocks are extrusive ( I think ????????, not sure but oh well )
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October 10th, 2006 at 9:40 am
Sandstone belongs to sedimentary. sandstone is for flooring and building. The grous within the family is Clastic, Organic, and Chemical. Sedimentiles they look like dirt but then they get compacked together and make sedimentary rocks. Sandstone rocks looks like kinda roundish and looks kind of smooth.
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October 10th, 2006 at 9:40 am
Ok metamorphic rocks are formed when the earths crust shifts and it causes other rocks are changed to metamorphic. Marble is a type of metamorphic rock It is Non foliated. Foliated rocks have like layers and Non foliated don’t. Marble is smooth, and its diffrent colors.
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October 10th, 2006 at 9:41 am
I am a expert in metamorphic rocks their are two types of rocks they are foliated and nonfoliated. I will tell you of both. Foliated is the composition of the original rock it is not apparent. Heat and minerals are creating new foliated rocks. Type of rocks that belong to foliated rocks are Schcist,and Gneiss. There is also nonfoliated which is the rocks can combine,change,or rearrange bu they don’t form paralell bands because they are composed mostly of one mineral. The type of rock that belongs to nonfoliated are Marble, and Quartzine.
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October 10th, 2006 at 9:41 am
an examle of sedimentary rock is chemical and an examle of chemical is gysum and it is formed when water is evaporated and minerals are left behind
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October 10th, 2006 at 9:43 am
-Sedimentary-
I am going to do limestone, Limestone is formed by little pieces left on the bottom of a evaporated water area. Limestone is composed of the mineral calcite. Limestones contain many fossils, The color of limestone is ablackish sorta color, and is manly used to make concrete. Limestone is Organic.
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October 10th, 2006 at 9:43 am
haha hi again……Sandston is a clastic rock
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October 10th, 2006 at 9:43 am
Obsidian rocks are in the Igneous family and are extrusive. It is extrusive because it forms outside of earth. Obsidian is black or brown, is smooth, and if it is thin enough it becomes trasparent. Igneous rocks are formed when lava or magma cools and forms crystles.
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October 10th, 2006 at 9:44 am
Sandstone forms from sand that sticks together. Sandstone is a clasic. Sandstone uses are aggregate in concrete and asphalt.
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October 10th, 2006 at 9:44 am
I am a expert in metamorphic rocks their are two types of rocks they are foliated and nonfoliated. I will tell you of both. Foliated is the composition of the original rock it is not apparent. Heat and minerals are creating new foliated rocks. Type of rocks that belong to foliated rocks are Schcist,and Gneiss. There is also nonfoliated which is the rocks can combine,change,or rearrange but they don’t form paralell bands because they are composed mostly of one mineral. The type of rock that belongs to nonfoliated are Marble, and Quartzine.
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February 13th, 2007 at 11:13 am
Pumice is an igneous rock that is extrusive. It comes in a lot of differant colors. There are many uses for pumice, including: cosmetics, construction, and landscaping.
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