Rocks and Minerals

A diamond is the only material that cannot be scratched by any other than itself.

It depends on the cooling of lava. Slow cooling forms big crystals deep under the surface while fast cooling creates small crystals on or just below the earths surface. Itstant cooling wouls have no crystals.

Metamorphic rock can turn into another type of rock through processes like weathering and erosion, which break down the rock into sediment. This sediment can then undergo compaction and cementation to form sedimentary rock, or melt and cool to form igneous rock through processes like metamorphism.

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Igneous rocks can weather and erode over time due to exposure to the elements. The eroded particles can then be transported and deposited by wind, water, or ice to form sedimentary rocks through processes like compaction and cementation.

Luster is categorized as metallic or non-metallic. Metallic luster is highly reflective, like chrome. Non-metallic is further divided by names such as dull, glassy, adamantine, waxy, silky, pearly, and greasy.

The main subcategories of metamorphic rock are foliated (such as schist and gneiss) and non-foliated (such as marble and quartzite). Foliated rocks have layers or bands due to the alignment of mineral grains, while non-foliated rocks do not have a layered structure.

Metamorphic rock forms from previously existing rocks that have been altered by intense heat and pressure. This process typically occurs deep within the Earth's crust where these conditions can transform existing rock types like sedimentary or igneous rocks into metamorphic rocks such as marble or gneiss.

Yes, sedimentary rock can undergo metamorphism due to heat and pressure, transforming it into metamorphic rock. If the metamorphic rock experiences further heat and melting, it can become igneous rock through processes like melting and solidification.

Heat from Earth's interior and pressure from overlying rock transform the remains of marine sediments into metamorphic rocks, such as slate, marble, or schist. This process, known as metamorphism, causes the minerals in the sediments to recrystallize and reorganize, resulting in a new rock with different properties than the original sediment.

Half gold rock may refer to a mineral called pyrite, also known as fool's gold. Pyrite is a brassy yellow mineral that resembles gold but has different properties, such as being harder and more brittle. It is commonly found in association with gold deposits.

When heat and pressure are applied to sandstone, the grains of sand compress and fuse together, leading to recrystallization of minerals and the formation of a new rock called quartzite. This process results in the sandstone becoming more compact, harder, and more durable.

Geodes are secondary structures that occur in sedimentary and igneous rocks.

Geodes are hallow on the insde.

They are spherical to oblate in shape.

Most contain clear crystals, though some may contain colored crystals.

Geodes are common in the U.S. states of Indiana, Iowa, Missouri, Kentucky and Utah, and the countries Mexico, Brazil, and Namibia.

Sedimentary rocks where just sediments like sand until an animal died and stuck there. The rock cycle says the rock goes lower in the earth. So when the animal died in just the right conditions it travelled down with the sediments as well. Compaction of this sediment made it rock. Surrounding the animal making a fossil. After a while the fossil turned into oil or coal. Metamorphic rocks are just heat applied rocks. This is the reason why it only happens in sedentary rocks instead of igneous or metamorphic.

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Sedimentary rocks form from sand and other materials eroded from rock, and precipitated minerals. These sediments may bury dead animals or plants and in time the sediment becomes rock, by compaction, de-watering and lithifying, with the buried remains becoming fossils within it.

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Oil and coal are fossil fuels formed from organic debris, but other fossils do not turn into them.

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Metamorphic rocks are formed from any other rock by heat and/ or pressure, not necessarily by heat alone; but metamorphism generally destroy any fossils in sedimentary rocks undergoing the change.

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Fossils cannot form in igneous rocks by definition: igneous rock is formed from its minerals in a molten state, mainly underground but also as volcanic lava which would obviously destroy any plant or animal it engulfs in erupting.

Most igneous rocks are harder than a penny, so it is unlikely that a penny would be able to scratch an igneous rock. Igneous rocks are typically composed of minerals like quartz and feldspar, which have a higher hardness than copper (the main material in pennies).

High temperatures and pressures, as well as the presence of fluids, can cause rocks to exhibit ductile deformation. This results in the rocks bending or flowing without breaking, usually in the deeper parts of the Earth's crust where these conditions are prevalent.

Minerals in metamorphic rocks can form due to changes in temperature and pressure, which cause existing minerals to recrystallize or new minerals to grow. The specific minerals formed depend on the original composition of the rock and the conditions under which the metamorphic process occurred.

Sediments in sedimentary rocks may be made of fragments of other rocks, minerals, and organic material like remains of plants and animals. These sediments are typically transported and deposited by processes such as erosion, weathering, and deposition.

Granite is already an igneous rock. If the granite simply melts and re-solidifies it will become granite again. If it melts and is erupted from a volcano, it will form rhyolite. If it melts and mixes with magma of a different composition, then it could form any number of igneous rocks.

Yes, a knife can cut through talc as talc is a soft mineral with a Mohs hardness of 1 on the Mohs scale. This makes it easy to cut or scratch with a knife because of its low hardness.

Rock layers are different and unique to each other due to the fact that each layer represents a time period. They are formed when rock, sediment, and minerals settle into one place for a long time and harden when another layer goes over it. Reading rock layers allow geologists to determine how much time has passed. They even sometimes tell of the history of the earth and all of the disasters that have occurred in each era.

Flint does not have cleavage because it is a microcrystalline form of quartz and does not exhibit cleavage like minerals with well-defined crystal structures. Flint tends to fracture conchoidally, producing smooth curved surfaces when broken.

Sedimentary rock forms near the Earth's surface without the influence of intense heat and pressure. It is typically composed of fragments of pre-existing rocks or organic material that have been compacted and cemented together over time.

Lava rock is generally safe for fish as it is inert and will not significantly alter water parameters. However, it is important to ensure that the rock is thoroughly cleaned before adding it to an aquarium to remove any dust or debris that could harm the fish. It is also recommended to test the rock with a weak acid (such as vinegar) to check for any carbonate content that may affect the water chemistry.