SPINEL (miniature)

Spinel is a mineral belonging to the larger spinel group, characterized by its magnesium and aluminum composition, with the chemical formula MgAl2O4 and a cubic crystal structure. The term "spinel" is derived from the Latin word "spinella," which means little thorn, reflecting the pointed nature of its crystals. This mineral crystallizes in the isometric system, typically forming twinned octahedra. While it lacks true cleavage, it exhibits octahedral parting and conchoidal fracture. Spinel has a hardness of 8 and a specific gravity ranging from 3.5 to 4.1, appearing in various colors, including red, lavender, blue, green, brown, black, and yellow, with some of the most notable gemstones being the Black Prince's Ruby and the Timur Ruby, both part of the British Crown Jewels. Historically, red spinels were often mistaken for rubies, a confusion that persisted until the 18th century when the term "ruby" became exclusive to the red variety of corundum. The name "balas" for certain red spinels originates from Balascia, an ancient region in Central Asia known for its rich deposits of these gemstones, particularly in the Gorno Badakhshan area of Tajikistan, which has been a significant source of red and pink spinels for centuries.