"In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form."
The study of the physical and chemical properties of minerals, including color, luster, hardness, specific gravity, and cleavage.
Crystallography: Study of crystal structures and their properties.
Mineral Formula: An expression of a mineral’s chemical composition.
Mineral Systems: A collection of related mineral species that share similar chemical and physical properties.
Crystal Habit: The external form of a mineral specimen.
Cleavage and Fracture: How minerals break apart in different directions.
Hardness: Physical property of minerals that describes their ability to scratch or be scratched by other materials.
Density and Specific Gravity: Measure of the mass of a mineral relative to its volume.
Color: The color of a mineral can be used to help identify it, although this is not always a reliable property.
Luster: The way that minerals reflect light.
Optical Properties: How minerals interact with light, including birefringence, polarization, and refractive index.
Twinning: The way that some minerals grow in parallel or interpenetrating crystals.
Magnetism: How some minerals can be attracted to a magnet.
Radioactivity: Some minerals contain radioactive elements that can be used in geological dating techniques.
Economic Uses: Many minerals have important industrial or economic uses, such as copper or iron.
Polymorphism: Minerals that have more than one crystal structure, depending on temperature and pressure.
Hardness: This refers to a mineral's resistance to scratching and is measured on the Mohs Scale, which ranges from 1-10.
Cleavage: The tendency of a mineral to break along smooth, flat planes when hit is called cleavage.
Lustre: The way a mineral reflects light is called lustre. It can be metallic, non-metallic, or glassy.
Color: The color of a mineral can help in its identification, but it's not the most reliable property.
Streak: This refers to the color of a mineral's powder when rubbed on an unglazed porcelain plate.
Specific Gravity: A mineral's weight compared to an equal volume of water is called specific gravity.
Crystal Form: The geometric shape of a mineral's crystal is called its crystal form.
Magnetism: Some minerals can attract iron, and these are called magnetic minerals.
Acid Reactivity: When a mineral reacts with an acid solution, it produces gas bubbles or dissolves.
Density: A mineral's density is its mass divided by its volume.
Refractive index: The amount of light that a mineral bends when it passes through is called its refractive index.
"The geological definition of mineral normally excludes compounds that occur only in living organisms."
"Some minerals are often biogenic (such as calcite) or organic compounds in the sense of chemistry (such as mellite)."
"Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks."
"The concept of mineral is distinct from rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale."
"A rock may consist of one type of mineral or may be an aggregate of two or more different types of minerals, spacially segregated into distinct phases."
"Some natural solid substances without a definite crystalline structure, such as opal or obsidian, are more properly called mineraloids."
"If a chemical compound occurs naturally with different crystal structures, each structure is considered a different mineral species."
"The International Mineralogical Association (IMA) is the generally recognized standard body for the definition and nomenclature of mineral species."
"As of July 2023, the IMA recognizes 5,955 official mineral species."
"The chemical composition of a named mineral species may vary somewhat due to the inclusion of small amounts of impurities."
"Specific varieties of a species sometimes have conventional or official names of their own."
"For example, amethyst is a purple variety of the mineral species quartz."
"Some mineral species can have variable proportions of two or more chemical elements that occupy equivalent positions in the mineral's structure."
"Sometimes a mineral with variable composition is split into separate species, more or less arbitrarily, forming a mineral group."
"The description of a mineral species usually includes its common physical properties such as habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, specific gravity, magnetism, fluorescence, radioactivity, as well as its taste or smell and its reaction to acid."
"Minerals are classified by key chemical constituents; the two dominant systems are the Dana classification and the Strunz classification."
"Silicate minerals comprise approximately 90% of the Earth's crust."
"Other important mineral groups include the native elements, sulfides, oxides, halides, carbonates, sulfates, and phosphates."
"Yes, there are other mineral groups besides silicates that are important and occur in the Earth's crust."