Gems of the Finest Water: Type IIA Diamonds

When French gem merchant Jean-Baptiste Tavernier first visited the Golconda diamond mines of India in the 17th century, the stones he saw there were unlike anything he had ever encountered. The diamonds had a special quality that he described as “gems of the finest water” in reference to their incredible limpidity. The diamonds that Tavernier purchased quickly made their way to the collection of Louis XIV, who incorporated them into the French crown jewels.

Today we use the much less romantic, but more scientifically accurate, term Type IIA to describe the distinctive diamonds that came from Golconda and other mines throughout the world. A Type IIA diamond is distinguished by its chemical purity. All diamonds are primarily carbon, but most also have traces of nitrogen which imparts a faint yellowish hue. Type IIA diamonds, which represent only 1% to 2% of all diamonds, have either very few or no nitrogen atoms. Their purity allows them to transmit ultraviolet and visible light that other diamonds block. We sometimes hear these stones referred to as “super Ds” because they seem so much better than other diamonds graded as D color, the top of the diamond color grading scale. Many of the world’s most important diamonds are Type IIA, including the Cullinan and the Koh-i-Noor.

Skinner is excited to offer two Type IIA diamonds in our December 8th Fine Jewelry sale. Both are from the collection of a prominent British-American family. According to family oral history, these stones were purchased by the patriarch in the 1880s or 1890s.  The first, Lot 494, was originally the center of the antique pendant that follows it in the catalog. The second, Lot 498, is probably the most exciting jewel in our sale: a 31.25 cts. heart-shape diamond which is D color and VVS2 clarity. Looking at this incredible stone, a quote by Elizabeth Taylor about her own Type IIA stone, the famous Krupp diamond, comes to mind: “[It] gives me the strangest feeling for beauty. With its sparks of red and white and blue and purple, and on and on, really, it sort of hums with its own beatific life.”