Aggregate β
A mass of mineral crystals or grains that are grouped together, rather than a single crystal.
Explore the fascinating properties, uses, and locations of Earth's most remarkable minerals.
A mass of mineral crystals or grains that are grouped together, rather than a single crystal.
The tendency of a mineral to break along flat, smooth surfaces determined by its internal crystal structure. Cleavage planes are areas of weak atomic bonding.
The classification of crystals based on their symmetry and geometric properties. There are seven crystal systems: cubic, hexagonal, tetragonal, orthorhombic, monoclinic, triclinic, and trigonal.
The emission of visible light by a mineral when exposed to ultraviolet (UV) light. The light stops when the UV source is removed.
The pattern in which a mineral breaks when it doesn't break along cleavage planes. Common types include conchoidal (shell-like), uneven, and splintery.
A mineral or organic material that has been cut and polished for use in jewelry or decoration. Valued for beauty, rarity, and durability.
A hollow, rounded rock containing crystals that grew inward from the walls. Often lined with quartz or amethyst crystals.
A measure of a mineral's resistance to scratching, typically measured using the Mohs scale (1-10). Diamond is the hardest natural mineral at 10.
Rocks or minerals formed from the cooling and solidification of molten magma or lava.
Any material that is trapped inside a mineral during its formation. Inclusions can be other minerals, gas bubbles, or liquids.
The way light reflects from the surface of a mineral. Common types include metallic, vitreous (glassy), pearly, silky, and dull.
Rocks or minerals formed by the transformation of existing rocks under high temperature and pressure conditions.
A mineral-like substance that does not demonstrate crystallinity. Mineraloids possess chemical compositions that vary beyond the generally accepted ranges for specific minerals.
A scale of mineral hardness from 1 (talc) to 10 (diamond), created by Friedrich Mohs. Each mineral can scratch those below it on the scale.
A mineral that is composed of atoms of a single element, occurring naturally in an uncombined form.
A naturally occurring mineral or rock from which a metal or valuable mineral can be profitably extracted.
The property of certain minerals to generate an electric charge when subjected to mechanical stress, or to deform when an electric field is applied.
Rocks formed from the accumulation and cementation of mineral and organic particles, often in water environments.
The largest group of minerals, characterized by silicon-oxygen tetrahedra (SiOβ) as their basic structural unit. Silicates make up about 90% of Earth's crust.
The ratio of a mineral's weight compared to an equal volume of water. It indicates how dense a mineral is.
The color of a mineral in powdered form, typically observed by rubbing the mineral on an unglazed porcelain plate.
The degree to which light passes through a mineral. Minerals can be transparent (clear), translucent (some light passes through), or opaque (no light passes through).
A sheet-like deposit of minerals that fills a fracture or crack in a host rock, often formed by hydrothermal fluids.