Ruby: The Regal Red Gemstone
Introduction
Ruby, the radiant red gem, is celebrated as July’s official birthstone and marks the 15th and 40th wedding anniversaries. A red variant of corundum, ruby stands distinct from all other corundum shades, which are classified as sapphires. Deriving its name from the Latin word ‘ruber’, meaning red, rubies have long adorned royal treasures and emblems. Interestingly, many historic royal jewels believed to contain rubies were, in fact, red spinels. Due to their vibrant hue and rarity, especially in larger sizes, rubies are among the most coveted and priciest gemstones.
Composition and Appearance
Corundum, the mineral family to which ruby belongs, is renowned for its hardness, ranking 9 on the Mohs scale, making it an ideal choice for diverse jewelry pieces. The entrancing red of rubies arises from the presence of chromium and iron. The shade can vary from a soft pinkish-red to a deep brownish-red, depending on the elemental concentrations. The most sought-after ruby shade, known as “pigeon’s blood”, is a pure red with a hint of blue. This exquisite hue is primarily found in the mines of Myanmar (Burma).
Origins
While the finest rubies are unearthed in Myanmar (Burma), Thailand, Sri Lanka, and Tanzania, other notable sources include:
- Afghanistan
- Cambodia
- Kenya
- Madagascar
- Vietnam
- Australia
- Brazil
- India
- Malawi
- Nepal
- Pakistan
- United States
- Zimbabwe
Properties and Enhancements
With a hardness of 9 on the Mohs scale, rubies are exceptionally durable, making them perfect for all jewelry forms.
Heat treatment is a common enhancement for rubies. Typically applied post-cutting, this treatment elevates the gem’s color and clarity. Some lower-grade rubies with surface-reaching fissures may undergo lead glass filling to improve their appearance.
Lab-grown corundum, replicating the ruby’s brilliant red, offers a cost-effective alternative with a chemical composition mirroring natural corundum. Additionally, there are ruby simulants in the market that mimic the gem’s iconic color but differ in chemical composition.
