Introducing the Dom Pedro Aquamarine

The one gem that can rival the Hope Diamond is finally on display at the Natural History Museum

Dom Pedro Aquamarine
Jeffrey Post, curator of the Smithsonian’s National Gem and Mineral Collection, says the size of the Dom Pedro Aquamarine is “unprecedented.” Donald E. Hurlbert/ NMNH, SI

You start with the stone, aquamarine, a word that means “seawater,” but not the deep-ocean blue that is the sea’s homage to the sky, nor the gray-green swells crashing on a shore, but the soft blue-green of a lagoon on a clear tropical morning. Chemically, it is almost identical to an emerald. What makes a stone one or the other is a handful of atoms scattered among the crystalline ranks: chromium for emerald, iron for aquamarine. Then you must have light. Aquamarine comes to life under the blues and cyans of daylight, as a ruby does near firelight. Next, consider the object itself, an obelisk of a little more than 10,000 carats, shot through with radiant starbursts of astonishing intricacy and precision. Thus you have described the latest addition to the Smithsonian’s National Gem and Mineral Collection, the Dom Pedro Aquamarine, one of the few objects in the world that can hold its own in a display case just 30 feet from the Hope Diamond.

Sometime in the 1980s, prospectors found the stone in a mine in the state of Minas Gerais in Brazil. Originally three feet long and weighing nearly 100 pounds, it was dropped by the prospectors, breaking into three pieces—two of which were sold by the mine owner to be cut into anonymous stones for jewelry. The largest piece escaped that fate; it was named the Dom Pedro, after the first emperor of Brazil, in the 19th century, and his son of the same name, who was the last. The stone traced a circuitous path to the German workshop of gem artist Bernd Munsteiner who, in the early 1990s, was moving toward using crystals as the raw material of sculpture, rather than for rings and pendants. The Dom Pedro presented both a challenge and a once-in-a-lifetime marketing opportunity, leaving him “fascinated and impressed.”

For four months, Munsteiner studied the crystal, sketching hundreds of designs. As a concept formed in his mind, he named his design Ondas Maritimas (“Waves of the Sea”). He drew dozens of grooves, or “negative facets,” at different angles, trapping the ambient light. At last he picked up a diamond-coated cutting wheel; it took some six months to turn the stone into a finished sculpture.

Then you have the people who saw the stone and fell in love with it, especially the American collectors Jane Mitchell and Jeffrey Bland, who bought the Dom Pedro in 1999. Although the value of the piece was incalculable—it was a unique example of an art form Munsteiner practically invented—it was still probably less than the exquisite stone would bring if it were cut up for jewelry, and Mitchell and Bland wanted to prevent that from happening. For most of the succeeding decade, it was out of public view, awaiting its apotheosis in the Natural History Museum. Fiber-optic lenses, fed by halogen bulbs tuned to the color of sunshine, illuminate it from above; light penetrates its blue-green depths and flashes among the meticulously incised grooves and facets, until the object itself almost disappears, like a green bottle dropping into the sea, leaving behind...light.

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