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Here you can learn more abourt the properties of the minerals

This is a student´s guide to Global Climate Change.

MINERALS

Talc is a phyllosilicate mineral that cleaves into thin sheets. These sheets are held together only by van der Waals bonds which allows them to easily slip past one another. This characteristic is responsible for talc's extreme softness, its greasy to soapy feel and its value as a high-temperature lubricant.
Rutile is a titanium oxide mineral that is most commonly found in granites, pegmatites and metamorphic rocks. It is also found in sands derived from the weathering of these rocks. Rutile also forms as slender crystals within quartz and micas. It is a common mineral in the alluvial sands that are dredged for magnetite and ilmenite.
Quartz is one of the most useful natural materials. Its usefulness can be linked to its physical and chemical properties. It has a hardness of seven on the Mohs Scale which makes it very durable. It is chemically inert in contact with most substances. It has electrical properties and heat resistance that make it valuable in electronic products. Its luster, color and diaphaneity make it useful as a gemstone and also in the making of glass. Quartz occurs in virtually every color. Common colors are clear, white, gray, purple, yellow, brown, black, pink, green, red.
Pyrite is a brass-yellow mineral with a bright metallic luster. It has a chemical composition of iron disulfide (FeS2) and is the most common sulfide mineral. It forms at high and low temperatures and occurs, usually in small quantities, in igneous, metamorphic and sedimentary rocks worldwide.
Olivine is the name of a group of rock-forming minerals that are typically found in mafic and ultramafic igneous rocks such as basalt, gabbro, dunite, diabase, and peridotite. They are usually green in color and have compositions that typically range between Mg2SiO4 and Fe2SiO4. Many people are familiar with olivine because it is the mineral of a very popular green gemstone known as peridot.
Magnetite is one of the most common oxide minerals and also one of the most common iron minerals. It is an important ore of iron and is found in igneous, metamorphic and sedimentary rocks. It can also be abundant in sediments.
Halite is the mineral name for the substance that everyone knows as "salt". Its chemical name is sodium chloride and a rock composed primarily of halite is known as "rock salt".
Gypsum is an evaporite mineral most commonly found in layered sedimentary deposits in association with halite, anhydrite, sulfur, calcite and dolomite.
Graphite usually occurs in flakes in metamorphosed rocks rich in carbon, but it can also be found in veins and in pegmatites. Where large deposits are found it is mined and used as an industrial lubricant and for 'lead' in pencils.
Native gold is an element and a mineral. It is highly prized by people because of its attractive color, resistance to tarnish and its many special properties - some of which are unique to gold. Its rarity, usefulness and desirability make it command a high price.
Galena is a lead sulfide mineral with a chemical composition of PbS. It is the world's primary ore of lead and is mined from a large number of deposits in many countries. It is found in igneous and metamorphic rocks in medium- to low-temperature hydrothermal veins. In sedimentary rocks it occurs as veins, breccia cements, isolated grains and as replacements of limestone and dolostone.
Fluorite is an important industrial mineral composed of calcium and fluorine (CaF2). It is used in a wide variety of chemical, metallurgical and ceramic processes. Specimens with exceptional diaphaneity and color are cut into gems or used to make ornamental objects.
Diamond is a rare, naturally-occurring mineral composed of carbon. Each carbon atom in a diamond is surrounded by four other carbon atoms and connected to them by strong covalent bonds. This simple, uniform, tightly-bonded arrangement yields one of the most durable substances known. Diamond is a fascinating mineral. It is chemically resistant and it is the hardest known natural substance. These properties make it suitable for use as a cutting tool and for other uses where durability is required. Diamond also has special optical properties such as a high index of refraction, high dispersion and high luster. These properties help make diamond the world's most popular gemstone.
Native copper is an element and a mineral. It is found in the oxidized zones of copper deposits; in hydrothermal veins; in the cavities of basalt that has been in contact with hydrothermal solutions; and as pore fillings and replacements in conglomerates that have been in contact with hydrothermal solutions. It is rarely found in large quantities, thus it is seldom the primary target of a mining operation. Most copper produced is extracted from sulfide deposits.
Chalcopyrite is a copper iron sulfide. It is the most commonly encountered copper mineral and is the most important ore of copper. Chalcopyrite deposits are found in hydrothermal veins, void fillings and replacements in limestones, contact metamorphic deposits and magmatic separations. Minor amounts are found throughout many igneous, metamorphic and sedimentary rocks.
Calcite is a rock-forming mineral with a chemical formula of CaCO3. It is extremely common and found throughout the world in sedimentary, metamorphic and igneous rocks. Some geologists consider it to be a "ubiquitous mineral" - one that is found everywhere. Calcite is the principal constituent of limestone and marble. These rocks are extremely common and make up a significant portion of Earth's crust. They serve as one of the largest carbon repositories on our planet.
Biotite is a name used for a large group of black mica minerals that are commonly found in igneous and metamorphic rocks. These include: annite, phlogopite, siderophyllite, fluorophlogopite, fluorannite, eastonite and many others. These micas vary in chemical composition but are all sheet silicate minerals with very similar physical properties.
Beryl is a beryllium aluminum silicate mineral most often found in granites and granite pegmatites. It can also be found in metamorphic rocks or in the veins and cavities of limestones and marbles. Beryl is the pimary ore of beryllium. Gem quality beryls with a specific deep green color are sold under the name "emerald". Different shades of green are known as "aquamarine" . Other gem quality beryls include: heliodore (yellow), morganite (pink) and goshenite (white).
Bauxite is not a mineral. It is a rock formed from a laterite soil that has been severely leached of silica and other soluble materials in a wet tropical or subtropical climate. It is the primary ore of aluminum. Almost all of the aluminum that has ever been produced has been extracted from bauxite.
Azurite is a deep blue copper carbonate. It serves as a minor ore of copper. It is also a popular gem and ornamental stone because of its blue color. Azurite's low hardness limits its use as a gem and as an ornamental stone. It is often found in association with malachite in the oxidized zone above copper deposits.