symmetry
There are 6 equivalent (111) planes in an orthorhombic crystal system. This is because in an orthorhombic crystal system, the axes are of different lengths and perpendicular to each other, creating 6 symmetrical orientations for the (111) planes.
Peridot (gem quality olivine (the mineral)) is in the orthorhombic crystal system.
Sulfur is an example of a mineral that crystallizes in an orthorhombic crystal system. Its atoms are arranged in a structure with three mutually perpendicular axes of differing lengths.
In crystallography, the orthorhombic crystal system is one of the seven lattice point groups. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with a rectangular base (a by b) and height (c), such that a, b, and c are distinct. All three bases intersect at 90° angles. The three lattice vectors remain mutually orthogonal. There are four orthorhombic Bravais lattices: simple orthorhombic, base-centered orthorhombic, body-centered orthorhombic, and face-centered orthorhombic.
Gypsum and orthoclase feldspar are in the monoclinic crystal system.
Six crystal classes are known.
Pyroxenes have a single chain structure, while amphiboles have a double chain structure. Pyroxenes typically have a simpler, more elongated crystal structure compared to the more complex, ribbony structure of amphiboles. Additionally, pyroxenes commonly have a monoclinic or orthorhombic crystal system, while amphiboles have a monoclinic system.
Crystal systems differ based on the arrangement of atoms within the crystal lattice. There are seven crystal systems: cubic, tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, and rhombohedral. Each system has unique geometric properties that define the shape of the crystals formed.
Peridot is typically found in small, elongated crystals with a flattened tabular shape. It belongs to the orthorhombic crystal system and often forms in granular aggregates or nodules in volcanic rocks.
The anhydrous barium chloride has an orthogonal crystalline structure.
Atoms within a mineral are arranged into an orderly geometric spatial arrangement known as crystal structure. There are 14 basic crystal lattices (refered to as the Bravais lattices) which fit into one of 7 crystal system (triclinic, monoclinic, orthorhombic, tetragonal, rhombohedral, hexagonal and cubic) and all observed minerals fit into one crystal lattice and one crystal system. Diamond on the other hand is an allotrope of carbon arranged into an isometric hexoctahedral (Cubic-type) crystal system.
Corundum is in the trigonal crystal system.