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Forensic gemology: Stephen Attaway’s research hobby casts new light on origins, history of Hope diamond

Forensic gemology: Stephen Attaway’s research hobby casts new light on origins, history of Hope diamond

For an engineer who makes his living doing vulnerability assessments and crunching numerical simulations of crashes and impacts using massively parallel computing, Stephen Attaway knows surprisingly a lot about the Hope diamond.

In fact, Stephen (9134), along with his wife Nancy and local diamond replica expert Scott Sucher, have recently completed a combination of historic and high-tech research that sheds new light on the life of the stone.

“There is a lot of mystery and intrigue about where the Hope came from,” says Stephen. “We closed some gaps in a history that a great many people are interested in. And we were able to create an accurate replica of the Hope and the predecessor stones we think it came from.”

So far the gem detective work, done completely as a hobby project at home, has garnered the attention of the Discovery Channel, which premiered a 30-minute documentary on the project last month, and Lapidary Journal, a key trade publication, which is in the process of publishing a paper authored by Nancy. Locals interested in cut gems in general and the Hope diamond in particular will have a chance to learn more this weekend at a display and show hosted by the Albuquerque Gem and Mineral Club.

Smithsonian cooperation

Stephen, Nancy, and Scott did their research in cooperation with the Smithsonian Institution’s National Museum of Natural History in Washington, D.C. Every year some seven million visitors come to the museum, many of them expressly to see the 45.5-carat Hope diamond. Jeffery Post, Smithsonian curator of gems and minerals, calls the research “exciting.” The work represents new information about the museum’s collection of 375,000 specimens, he says. “We are constantly learning new things about our collections as we apply new high-tech research methods. Even the Hope diamond is grudgingly giving up some of its secrets.”

The researchers used state-of-the-art imaging and computer modeling technology, new measurements of the Hope, and historical records and sketches of two historic diamonds to create accurate virtual models of the three. “We were invited by the Smithsonian to photograph the Hope out of its setting. We even got to hold it in our hands. But we didn’t get to hold it very long,” says Stephen.

A highlight of the trip was a personal tour through the cut gem collection in the Smithsonian vault. “For Nancy, who has a long interest in gems and is an expert gem cutter, this was a once-in-a-lifetime chance,” says Stephen. And the data from the trip proved critical to the result of the project. It supports the theory that the Hope was cut from the French Blue Diamond, stolen from the French crown jewels in 1792.

A ‘sister diamond?’

Many have speculated over the years that a second blue diamond, or “sister diamond,” cut from the same “parent stone,” could still exist in a collection somewhere in the world. To understand this, you have to follow the history, beginning with the Tavernier Blue, named after a gem merchant who sold King Louis XIV of France a 112-carat blue diamond from India in 1668. A court jeweler cut the famous 67-carat French Blue out of the Tavernier. It became part of an ornate item of jewelry worn by European royalty until 1792, when it was stolen.

From here history slips into mystery, although most believe that the Hope came into being in the early 1800s when it was re-cut at 45.5 carats from the French Blue in London. (Henry Philip Hope was a diamond collector who owned the stone, hence the name.)

Collectors, doing the math from 67 to 45 carats, wondered if perhaps there could be a large sister stone to be found after the re-cut.

Stephen and his colleagues approached the problem with the idea of constructing, as accurately as possible, virtual and real models of the three historic diamonds. They used books from Tavernier’s travels in India, historic sketches, articles from a French gemology review, data about the lead molds used in creating Louis XIV’s jewelry, and some modern technology. In the case of the French Blue, Stephen generated 14 different iterations of what the diamond might look like based on known data about it, using CAD software, and finally finding a good match of the known dimensions and weights.

Mystery resolved

Using 30 photos of the Hope from their Smithsonian trip, Stephen applied 3-D photo measurement software to generate an accurate rendition. The model showed that the Hope did fit within the French Blue, tightly and only in one way.

Using the software models, Scott cut a model of the Travernier, and Nancy cut a model of the French Blue, both from dark blue cubic zirconia. These replicas were given to the Smithsonian, where they will eventually be displayed near the Hope diamond. Then, by creating molds of the three diamonds using a lost-wax process, the team demonstrated the unlikelihood of a sister diamond. “We believe the diamond material lost during the re-cutting of the French Blue to the Hope was ground into powder,” says Stephen.

Although this is not what the Discovery Channel wanted to hear, the program’s originators were able to make an interesting 30-minute segment out of the effort. “They were convinced the other half of the Hope was out there and they were hot on the trail of it,” says Stephen. “In fact, we proved the opposite of what they wanted.” A film crew spent three days in Albuquerque, helping to give Stephen, Nancy, and Scott their 15 minutes of fame. “It was an interesting process,” says Stephen, “but I learned that I’m not an actor.”