Black Spinel Round Faceted Stones


This petite round black spinel is a budget-friendly alternative to black diamond and other more expensive black stones; the hardness makes it an appropriate choice for adding dramatic black stones to any type of jewelry, even those that get the most wear. Black spinel, an opaque variety of vitreous magnesium aluminum oxide, is relatively hard (an "8" on the Mohs hardness scale) and takes a high polish, giving it an appearance similar to more costly black gemstones. Because the stone is opaque it has no refractive brilliance but, with a high polish, the facet can reflect light for an attractive presentation. In folklore, black spinel is believed to be protective, assuaging sadness and rebuilding relationships.

Named for its spiky crystal structure from the Latin "spina" (meaning "thorn"), spinel is a vitreous magnesium aluminum oxide. Hard, durable, and occurring naturally in a range of transparent colors, spinel is a versatile stone for all forms of jewelry.

Round-cut gemstones are highly popular and the most commonly available. Rio round gemstones are calibrated for size and hand inspected to ensure maximum attractiveness.

  • Cutting Center : Germany
  • Mineral source : China
  • Stone(s) shape : Round
  • Material : Spinel
  • Stone type : Natural
  • Color : Black
  • Clarity : Opaque
  • Mohs hardness : 7.5–8
  • Refractive index : 1.712–1.762
  • Enhancement : None (N)
  • Specific gravity (g/cm3) : 3.52–3.66
  • Stone type : Natural

Please Note: • Unless precisely calibrated to an exact size, gemstone sizes vary slightly. Rio allows a tolerance of +/– 0.1mm for gemstones 4mm and smaller.
• Clean with warm, soapy water. Ultrasonic cleaning is usually safe; never steam clean.

Catalog page: 2019-2020 Gems and Findings & Display and Packaging Catalog p.710