It looks like you are asking about spinel, a beautiful and highly valued gemstone, rather than “spinal.†Hereâ€TMs a detailed description of spinel:

Spinel Gemstone Description

Spinel is a rare and durable gemstone known for its vibrant colors, brilliance, and historical significance. It is composed of magnesium aluminum oxide (MgAlâ‚‚Oâ‚„) and forms in octahedral crystals. Often mistaken for rubies and sapphires in the past, spinel has gained recognition as a distinct and valuable gem.

Key Characteristics of Spinel

• Color:

• Found in red, pink, orange, blue, purple, violet, and black.

• Red spinel is the most famous, resembling ruby but with a slightly different glow.

• Blue spinel can rival sapphire, especially when rich in cobalt.

• Hardness: 7.5 – 8 on the Mohs scale (durable, but slightly softer than ruby and sapphire).

• Luster: Vitreous (glassy) and highly reflective.

• Clarity: Typically eye-clean, meaning it has minimal visible inclusions.

• Refractive Index: 1.71 – 1.76, giving it excellent brilliance.

• Formation: Found in metamorphic and alluvial deposits, often alongside rubies and sapphires.

• Sources:

• Myanmar (Burma) – Produces some of the finest red spinels.

• Sri Lanka – Known for a variety of spinel colors.

• Tanzania, Vietnam, Afghanistan, and Madagascar – Important sources of high-quality spinel.

Historical Significance

Spinel was historically mistaken for ruby, and many famous “rubies†in royal collections are actually spinel. Examples include:

• The Black Princeâ€TMs Ruby – A large red spinel set in the British Imperial State Crown.

• The Timur Ruby – Another famous red spinel once owned by Mughal emperors.

Spinel vs. Other Gemstones

• Spinel vs. Ruby – Both can be deep red, but spinel is usually lighter and lacks rubyâ€TMs strong fluorescence.

• Spinel vs. Sapphire – Blue spinel can resemble blue sapphire, but sapphire is harder and has a slightly different refractive index.

Value and Uses

• Used in high-end jewelry, including rings, necklaces, and royal regalia.

• More affordable than ruby and sapphire, but fine specimens are still highly valuable.

• Rarely treated or enhanced, making natural spinel highly sought after.

• August birthstone (alongside peridot and sardonyx).

Would you like a comparison between spinel and another gemstone, like ruby or sapphire?