Rock composed of layered bands of sediment is called sedimentary rock. Erosion creates sand, clay, silt and other sediment. Sediment builds up, and with the passage of time, the layers are compacted and cemented together to form sedimentary rock.
A:Mine-cut diamonds are typically square or slightly oval and have a deeper crown and pavilion, or top and bottom, than modern stones. "Mine cut" does not refer to the place the diamond was faceted, but rather to its overall shape and brilliance.
A:Chemical weathering is the process by which a material breaks down into its component elements through the action of a chemical agent. This type of weathering requires precise temperature conditions and the presence of a chemically-laden fluid. Substances capable of causing chemical weathering include water and acids.
A:The hardest natural mineral in the world is lonsdaleite, a rare mineral made of carbon atoms. This mineral can withstand up to 58 percent more stress than diamond, according to a report by Jessica Griggs of NewScientist.
A:A plateau is formed by a process of geological uplift, either due to the collision of continental plates, pressure from magma below or the burial of land by volcanic lava and ash flows, resulting in a high, flat surface. These are very similar to processes that give rise to mountains and mountain ranges. The only major difference is that a plateau is flat while mountains are peaked.
A:Most meteorites that fall to Earth come from the asteroid belt between Mars and Jupiter, where they formed during the early days of the solar system. Occasionally, collisions or gravitational perturbations send one of these objects hurtling toward the sun. If it approaches close to Earth, it may fall into the planet's gravity well.
A:Shale forms from the pressure of layers of sediment compressing bits of silt that settle into the clay on the bottom of bodies of water. The compressed clay and silt become shale over time. Shale is a sedimentary rock.
A:Possible parent rocks of gneiss are granite, shale, gabbro or diorite. Some rocks metamorphose, or change, from one particular kind of rock, but gneiss forms from one of several types. Another name for the parent rock is the protolith.
A:A mineral resource is the concentration of materials that are of economic interest in or on the crust of the Earth. Almost all minerals found on Earth are used in one way or another for economic benefit. Examples of minerals include gold, gravel, sand, aluminum, copper, limestone, clay and diamond.
A:To turn copper green, create a verdigris paina by rubbing the metal with a vinegar and salt solution. Before you begin, gather some steel wool, a bowl, paper towels, dish soap, baking soda and a finishing wax or lacquer.
A:Salt, or sodium chloride, is a non-renewable resource. A resource is defined as renewable only if it is self-replenishing. While new salt is being formed by natural processes in the earth, the timescale for that formation is too vast for salt to be considered self-replenishing in terms of human use.
A:Coal reserves exist in every country in the world and on every continent except Antarctica. According to the World Coal Association, there are enough coal reserves to meet current demand for 112 years, but only enough oil and gas reserves to meet current demand for the next 46 and 54 years, respectively.
A:Minerals are formed under a variety of conditions, including when molten materials cool, when liquids evaporate or cool and under high temperatures and pressures. Minerals are found in the earth's crust and mantle, and many were created when feldspar and quartz reacted with other materials during the formation of the planet.
A:Fossil fuels are formed the gradual accumulation of organic remains on the sea floor. As the accumulation rate increases, the organic remains are subjected to heat and pressure, which leads to fossil-fuel formation.
A:Igneous rocks are often used for construction because of their durability. Igneous rocks can also be separated to access the various valuable metals and minerals inside them. Igneous rocks form as magma comes to or near the surface of the Earth; cooling and hardening because of its distance from the inner parts of the Earth where magma forms.
A:The molecular structure of a diamond makes it hard, as diamonds are comprised of carbon atoms linked closely together in a lattice structure. The atoms are linked tightly via covalent bonds wherein two atoms share an electron. A tetrahedral unit is composed of five carbon atoms, with one carbon atom sharing electrons with the other four. An extremely strong molecule is formed from the tetrahedral bonding of five carbon atoms.
A:Granite has a coarse to very coarse grained texture. It is typically granular and can be porphyritic with well-shaped large crystals of feldspar. Its structure contains cavities wherein well-formed crystals project.
A:Real silver is identified by its sound, its lack of magnetic qualities and by its ability to conduct heat. For instance, when tapped together, two silver coins emit a high, clear tone. The bell-like ring continues for a second or two.
A:Minerals are solid, naturally occurring, inorganic compounds that possess an orderly internal structure and a regular chemical composition. A mineral species has to possess these five characteristics to be regarded as scientifically valid.
A:Rocks come from magma, which is the molten material found within the earth. When magma cools, either above or below the earth's surface, it crystallizes and forms the igneous rocks that can later be changed into metamorphic or sedimentary rocks. Magma, which can be considered molten rock, is referred to as lava when it reaches the earth's surface.
A:The most common type of coal is anthracite, which has a hardness of 2.2 when compared to the Moh's scale of mineral hardness, according to the Ted Pella website. However, since coal is not a mineral, it is not officially measured in this way.