Largest Aquamarine Specimen Ever Found in North America Donated to Denver Museum of Nature & Science
“Diane’s Pocket” Specimen to be Unveiled at “Museum After Dark” Fundraiser on Friday, November 10, Put on Public Display on Friday, November 17
DENVER—November 10, 2006—The Denver Museum of Nature & Science has received a spectacular new donation to its gem and mineral collection: the largest aquamarine specimen ever found in North America.
The reconstructed specimen consists of more than 100 aquamarine crystals and other gems. It was discovered in 2004 by a lone prospector in a claim known as “Diane’s Pocket” near the summit of Mount Antero in the Sawatch Range of central Colorado. It will be unveiled at the Museum’s annual “Museum After Dark” fundraising dinner on Friday, November 10, and will go on permanent public display in the Coors Gem and Mineral Hall on Friday, November 17.
The aquamarine was donated by Museum trustee and avid mineral collector Bruce Oreck, and his wife Cody. Funds for the exhibition of “Diane’s Pocket” were generously donated by Newmont Mining Corporation, Hadley Stuart, Jr., Cortlandt S. Dietler, and many other friends of the Museum’s gems and minerals collection.
The “Diane’s Pocket” specimen is dazzling both to mineral enthusiasts and to scientists. “To find a pocket that’s that big and that complete really extends our knowledge of the formation of aquamarine and the nature of the geologic structure up on Mount Antero,” said Dr. Kirk Johnson, the Museum’s chief curator and vice president of research and collections. “It’s a phenomenal thing that people can go out and find treasures like this in the Colorado mountains today. That’s what science is all about—we’re continually making new discoveries. It’s not all last year, or last century. It’s happening right now and right here in Colorado.”
The “Diane’s Pocket” reconstruction on display at the Museum measures 37 inches by 25 inches, and features some of the largest and finest aquamarines ever found in North America. The specimen also contains white feldspar, silvery mica, and red garnets, and dozens of black quartz crystals. The rock cavity—or vug—where these crystals formed was discovered in 2004 by prospector Steve Brancato who works a claim near the summit of Mount Antero, Colorado’s 10th highest peak. He named it “Diane’s Pocket” as a tribute to his mother.
“To be able to remove it and reconstruct it for the Museum, that was always my intention,” said Brancato. “I figure it’s not just here for my pleasure. It’s here for all of us to see. I’m just honored to be the one to bring it out. I love the thought of little kids generations from now getting inspired by looking at it and maybe they’ll decide to come up here and find something even better.”
The promise of finding treasure has lured prospectors to Mount Antero and its neighbor, White Mountain, since the 19th century. Initially, they were hunting for veins of gold and silver. What they found instead were rare sea-green and sky-blue crystals—aquamarines. These minerals have a hexagonal crystal structure and are closely related to emeralds. Both are gemstone-quality varieties of the mineral beryl.
Aquamarines form under very specific, violent geologic conditions. Thirty-five million years ago, mineral-rich magma under high pressure intruded from below into the rock layers of the Sawatch Range. As the magma cooled, it trapped cavities of mineral-saturated fluid heated to temperatures as hot as 600° C (1,112° F). Minerals, including aquamarines, crystallized out of that fluid in these pockets. Over millions of years, the mountains were uplifted and eroded, which exposed the pockets and the crystals within them. Most of the time, it is difficult for scientists to say precisely what an aquamarine cavity looked like because the crystals break off the cavity walls over time. The cavities themselves collapse as they are jostled by seismic activity and exposed by erosion.
This was also the case with “Diane’s Pocket.” While a few aquamarine crystals were still attached to the vug wall, most were lying on the floor of the pocket when Brancato discovered it. Brancato collected the crystals and buckets of rock from the pocket and hauled it down the mountain. The geologists and gemologists at The Collector’s Edge in Golden, Colorado agreed to work with the Denver Museum of Nature & Science to re-create what part of “Diane’s Pocket” might have looked like when it formed. This involved cleaning, sorting and numbering each piece of rock and crystal from “Diane’s Pocket,” and reassembling the pieces using scientific knowledge and a little artistic license. The entire process took more than six months to complete.
“The Museum is the place where we collect the treasures of Colorado for everyone to see and enjoy, so we feel particularly fortunate to have this stunning Colorado discovery donated to our collection,” said George Sparks, President & CEO of the Museum. “Since the aquamarine is Colorado’s state gemstone, it is very special that we can display this awe-inspiring specimen in the Coors Gem and Mineral Hall.”
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About the Denver Museum of Nature & Science: The Denver Museum of Nature & Science is the Rocky Mountain Region’s leading resource for informal science education. A variety of engaging exhibits, discussions and activities help Museum visitors celebrate and understand the natural wonders of Colorado, Earth and the universe. To learn more about the Museum, log on to www.dmns.org.
Many of the Museum’s educational programs and exhibits are made possible in part by generous funding from the citizens of the seven-county metro area through the Scientific & Cultural Facilities District.
