Djeva Fire Blue Lab Spinel, House Of Sylas Cushion Cut, 25 Carats


Regular price$780.00
Shipping calculated at checkout.

Gem Note

💙💙💙 The Djeva 114 cobalt-doped blue spinel, sourced from the renowned yet now-defunct Swiss company, represents the pinnacle of cobalt spinel coloration. This gem's color can best be described as velvety—deeply saturated yet radiantly bright, capturing the essence of a rare jewel. This remarkable lab-grown spinel, with its intriguing history, offers the perfect opportunity to create a piece of jewelry that is not only spectacular but also enduring. Transform this extraordinary gemstone into a timeless treasure that will be cherished for a lifetime.



Size: 16.45mm x 16.36mm x 12.45mm

Weight: 25.0  carats

Cut: House Of Sylas Cushion

Shape: Cushion

Clarity: Loupe Clean

Inclusions: None

Treatment: None



MOHS hardness: 8.25


Dispersion: 0.018

Density: 3.61

Refractive Index: 1.72

Chemical Formula: MgAl2O4


  • Pendant
  • Cocktail Ring
  • Daily Wear


  • Vivid
  • Djeva


  • Material Name:Djeva 114
  • Country of Origin : Switzerland
  • Growth Method: Flame Fusion

Djeva's "Fire Blue" cobalt spinel stands out as the most vibrant and deeply colored blue gemstone material available. While cobalt glass shares a similar intensity in color, it falls short in terms of refractive index, dispersion, and durability.

The flame fusion cobalt spinel is essentially a type of beta-corundum. The process of cultivating a pure spinel crystal through flame fusion may lead to cracking as it cools. However, integrating additional alumina powder (corundum powder with a Mohs hardness of 9) into the mix enhances the crystal's resilience and strength, preventing it from cracking upon cooling. This modification not only fortifies the crystal but also elevates its hardness to a Mohs rating of 8.25, surpassing the typical hardness of standard spinel.

Cobalt blue spinel presents a fascinating characteristic of red fluorescence. While some specimens exhibit this glowing feature, others do not; however, all of them display vivid red flashes when illuminated under full-spectrum lighting. This phenomenon is truly intriguing!


Djeva 114 "Fire Blue" holds a unique place in gemstone lore, with its production having ceased. Presently, several manufacturers of cobalt flame fusion spinel endeavor to match the luminosity of Djeva's creation, yet none have achieved comparable brilliance. The only other option is spinel grown through the Czochralski method, which comes with a steep price tag. For those seeking a dazzling blue gem that combines beauty with durability to stand the test of time, this material might just be the ideal choice.

  • In stock, ready to ship
  • Backordered, shipping soon

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Djeva Fire Blue Lab Spinel, House Of Sylas Cushion Cut, 25 Carats
Djeva Fire Blue Lab Spinel, House Of Sylas Cushion Cut, 25 Carats
Djeva Fire Blue Lab Spinel, House Of Sylas Cushion Cut, 25 Carats
Djeva Fire Blue Lab Spinel, House Of Sylas Cushion Cut, 25 Carats

Recently viewed

You may also like

🧠 Gemology Literature

The articles cited here about lab created gemstones are all open source and chronologically sorted for quick and easy access. Each article comes from either the Journal of Gemmology (JofG) or Gems and Gemmology (G&G) archives.