Spinel is a durable and brilliant gemstone found in a wide variety of colors, including red, pink, blue, purple, and orange, which is the result of trace elements like chromium and iron. It is a hard mineral, ranking 8 on the Mohs scale, making it suitable for jewelry, and is characterized by its cubic crystal system and octahedral shape. Historically, high-quality red spinels were often mistaken for rubies.

Appearance and composition

• Color:

  Spinel comes in a vast range of colors, with some of the most sought-after being vibrant reds and pinks, which are caused by chromium. Other colors include blue (from iron), violet, green, orange, and black.

• Composition:

  It is an oxide mineral composed of magnesium, aluminum, and oxygen, with other trace elements influencing its color.

• Brilliance:

  Spinel is known for its brilliance and vibrancy, thanks to its high refractive index.

Physical and geological properties

• Hardness: It has a Mohs hardness of 8, making it a durable choice for jewelry.

• Crystal system: Spinel belongs to the cubic crystal system and often forms in a perfect octahedral shape, which resembles two pyramids joined at the base. The name "spinel" comes from the Latin "spinella," meaning "little thorn," due to its sharp crystal formations.

• Refractivity: Spinel is a singly refractive mineral, meaning it doesn't split light into two rays.

History

• Confusion with ruby:

  For centuries, many famous red gems were thought to be rubies, but modern gemology has identified them as spinels.

• Underrated status:

  Spinel was historically overlooked and undervalued, partly due to this confusion and being one of the first gems to be synthesized.