Liquid or molten rock deep in the earth in a zone of very high temperatures and enormous pressure where rock fusion takes place (Upper Mantle).

A malleable and ductile silvery white metal that is used in alloys.

Branch of physics that studies the properties of magnets and magnetic fields.

Capable of being hammered into thin sheets.

A habit made up of large, curved surfaces that resemble rounded breasts.

Crystal masses that are so fine and minuscule that they are almost imperceptible.

Irregular form, showing crystal or cleavage faces, but with no euhedral crystals.

The rock or mineral surrounding a particular crystal or group of crystals.

Minerals whose crystal structure has been partially destroyed by radiation from contained radioactive elements.

Having a luster resembling polished metal.

Having lost crystal structure due to the influence of radioactivity, while retaining the outward form of the crystal.

Changes over time in the composition and structure of rocks caused by pressure and temperature.

A branch of philosophy and related to natural sciences, like physics, psychology, biology of the brain and also to mysticism and religious and spiritual subjects. It is notoriously difficult to define, but for purposes of briefly introducing it to non-philosophers, it can be identified as the study of any of the most fundamental concepts and beliefs, on which many other concepts and beliefs rest; concepts such as being, existence, universal, property, relation, causation, space, time, event and many others.

An object, usually a chunk or metal or rock, that survives entry through the atmosphere to reach the Earth's surface. Meteors become meteorites if they reach the ground.

A potentially explosive gas formed naturally from the decay of vegetative matter, similar to that which formed coal. Methane, which is the principal component of natural gas, is frequently encountered in underground mining operations and is kept within safe limits through the use of extensive mine ventilation systems.

Sparkling, flaky masses that aggregate together like sheets of paper.

Having crystal grains only visible under a microscope.

Very small, usually affixed permanently to a pedestal in a display container (traditional North American style) with putty or other adhesive material.. These specimens need magnification to be viewed. The matrix itself is often smaller ¼ inch.

A plant built to extract an ore or mineral substance either underground or from the surface. When the ore is extracted underground, the mine needs a system of excavations in the rock to gain access to the ore areas. When the ore is mined from surface, the ore is extracted from one or several pits.

One who is engaged in the business or occupation of extracting ore, coal, precious substances, or other natural materials from the earth's crust.

An inorganic natural substance is characterized by its atomic structure and physical and chemical properties.

Mineralized mass that may be economically valuable, but whose characteristics require more detailed information. An orebody being mined may be called a deposit.

Specimens from 1¼ to 2¼ are considered miniatures. This category includes any specimen too small to be considered "Small Cabinet" size but too large to fit in a "perky box". This size fits easily in a 2½ x 2½ x 2½ inch plastic box.

Activity whose purpose is the extraction, concentration, and smelting of economic minerals from a mineral deposit. It includes exploration (in the strict sense), development of mineral deposits, constructing the mine and mining, i.e., extracting and processing the ore or tailings.

A crystal face truncated by another face, as in an octahedron modified by a cube.

Minerals containing the molybdate (MoO₄) radical as a major component.

A crystal system having three unequal axes, two at an oblique angle and
a third at right angles to those two.

A unit of pattern.

Mine Safety and Health Administration; the federal agency which regulates mine health and safety.

A charge of high explosive fired in contact with the surface of a rock after being covered with a quantity of wet mud, wet earth, or sand, without any borehole being used. Also termed adobe, dobie, and sandblast (illegal in coal mining).

If a fumarole emerges under surface water the hydrogen sulfide in the steam is oxidized in the water both by chemical reactions and bacteria to make sulfuric acid. The sulfuric acid dissolves the nearby rock making wet, muddy clay. As the steam bursts through the clay, the bubbling action of the mud pot is created. Depending on the amount of surface water available, mud pots can change in consistency with the season.

Usually a very large specimen, often showing spectacular crystals or form.