A mineral is an inorganic, crystalline solid. A mineral is formed through natural processes and has a definite chemical composition. Minerals can be identified by their characteristic physical properties such as crystalline structure, hardness, density, flammability, and color.

mineral

Definition of a Mineral: With a definite chemical composition (every time we see the same mineral it has the same chemical composition that can be expressed by a chemical formula). and a characteristic crystalline structure (atoms are arranged within the mineral in a specific ordered manner).

A crystalline structure is any structure of ions, molecules, or atoms that are held together in an ordered, three-dimensional arrangement. Crystalline structure is one of two types of structural ordering of atoms, the other being the amorphous structure.

With rocks being made up minerals as opposed to crystals they do not have a crystal structure. Rock types are divided into three main groups which are sedimentary, igneous and metamorphic.

Crystalline rock refers to both igneous and metamorphic formations that consist of tightly interlocked grains of minerals that have formed by crystallization from a melt or solid-state reactions at elevated pressures and temperatures.

In geology, basement and crystalline basement are the rocks below a sedimentary platform or cover, or more generally any rock below sedimentary rocks or sedimentary basins that are metamorphic or igneous in origin.

Igneous rocks may be simply classified according to their chemical/mineral composition as felsic, intermediate, mafic, and ultramafic, and by texture or grain size: intrusive rocks are course grained (all crystals are visible to the naked eye) while extrusive rocks may be fine-grained (microscopic crystals) or glass ( …

Coarse-grained hard igneous crystalline rock composed of feldspar, mica, and quartz, usually grey or dark red, and capable of taking a high polish.

Crystalline Rocks Crystalline sedimentary rocks are composed of crystals having formed from a chemical reaction in a solu- tion or from evaporation. The crys- tals can vary in size from very fine (you cannot see them with the na- ked eye) to very coarse. An example of the crystalline rock rock gypsum is pictured below.

Crystalline sedimentary rocks form from chemical reactions in which minerals within water form crystals and precipitate out of the solution.

Sedimentary rocks are formed due to the transportation and deposition of sediments in river beds. Crystals require very high temperatures to form but there is no thermal process in sedimentary rock formation. This is why Sedimentary rocks don’t form crystals while igneous rocks form crystals.

Common Sedimentary Minerals

Sedimentary rock is classified into two groups based on how they form. They are clastic and chemical. Clastic sedimentary rock is formed as bits of weathered rock become cemented together. Chemical sedimentary rocks form when minerals that are dissolved in water become deposited as solids.

red and yellow soils are formed due to the weathering of crystalline igneous rocks.

Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.

As magma cools, minerals typically crystallize from the melt at different temperatures (fractional crystallization). As minerals crystallize, the composition of the residual melt typically changes. If crystals separate from the melt, then the residual melt will differ in composition from the parent magma.