With more than 10,000 gems, the Smithsonian’s National Gem Collection is brimming with breathtaking stones like the scintillating Whitney Flame Topaz, the radiant Carmen Lúcia Ruby and the iconic Hope Diamond. But mineralogist Jeffrey Post, the National Museum of Natural History’s curator-in-charge of gems and minerals, thinks the collection's newest addition will stop museum visitors in their tracks.“Things like this get people to stop and look,” Post says of the Lion of Merelani, a glowing green gem unveiled this week in the museum’s Janet Annenberg Hooker Hall of Geology, Gems, and Minerals. The new showstopper is the world’s largest square-cushion cut tsavorite (the first "t" is silent) gem with 177 glimmering facets.
In addition to its staggering size — the stone is more than twice as heavy as the Hope Diamond — the Lion of Merelani’s verdant hue makes it a rarity. The gem is a garnet, a group of silicate mineral crystals that have been used as precious gemstones since the Bronze Age 5,000 years ago. Most garnets are prized for their rich red hues — the word “garnet” comes from the Latin word for pomegranate, whose dark seeds resemble the crimson crystals.
So when geologist Campbell Bridges discovered glassy green garnets in the hills of northeastern Tanzania in 1967, he knew he had unearthed something spectacular. “When he discovered this green garnet it really did shock the world,” Post said. “It was not something people had thought about when it came to garnets.”
Like other garnets, the green variety is formed when heat and pressure deep within the Earth transform rock. Most of these metamorphic rocks are hundreds of millions of years old and date back to when eastern Africa was on the margins of a splintering supercontinent. By mapping these rocks across local deposits, Bridges was able to also find the green garnet-bearing in Kenya in 1970. There, he soon found green garnet crystals large and transparent enough to be fashioned into gemstones.
While he was out excavating garnets, a leopard would often enter Bridge’s treehouse and devour its meal on his bed. Bridges later wrote that when he returned for the night, the leopard would “express his displeasure by walking around the tree at night, growling and clawing at the bark.”When he wasn’t sharing a tree house with a leopard in the African bush, Bridges spent time in northern Virginia. In between his excavations, he would collaborate with Smithsonian geologists to study his latest finds. The first analysis of the green garnets from Kenya was conducted by George Switzer, the Smithsonian mineralogist who started the National Gem Collection and acquired the Hope Diamond. Switzer helped determine that the mineral’s vivid green color was tied to trace amounts of the element vanadium. Bridges also worked with experts at the Tiffany and Company to promote these stones as exquisite jewelry in the early 1970s.
Bridges and experts at Tiffany and Company proposed that the “magnificent fiery green gemstone” be named tsavorite after the Tsavo National Parks that straddle the border of Kenya and Tanzania. In 1898, a ravenous pair of man-eating lions made the Tsavo region famous as they terrorized a group of local railroad workers for months.
Tsavorite soon became the Tsavo region’s other claim to fame: all of the world’s gem-bearing tsavorite deposits are concentrated in close proximity to the region. To sustainably harvest the exceptionally rare garnets, Bridges established the Scorpion Mine in Kenya. The mine is still operated by his company, Bridges Tsavorite.
Rich tsavorite deposits are also found around the gem-mining outpost of Merelani in northern Tanzania. In 2017, miners unearthed a cocoon-shaped tsavorite crystal bigger than a D-size battery. The glimmering piece of rough weighed more than 283 carats — more than enough crystal to create a mammoth gemstone. It soon found its way to a gem show in Hong Kong, where it was shown to Campbell Bridges' son, Bruce.
“When I first put my gem light to the piece I immediately knew what I had before me,” Bruce Bridges says. “My initial impression was that this fabulous piece of rough would yield a vivid kryptonite-colored green gem well in excess of 100 carats.”
After purchasing the prodigious piece of rough, the younger Bridges, now CEO of Bridges Tsavorite, teamed up with Somewhere in the Rainbow (SITR), a privately owned colored gem and jewelry collection with an emphasis on education. “Although Somewhere In The Rainbow rarely acquires rough gem materials, the opportunity to honor Campbell Bridges and the legacy of Tsavorite Garnet, was impossible to resist,” says Shelly Sergent, the curator of SITR.
Bridges and SITR then employed the services of world-renowned gem cutter Victor Tuzlukov to transform the rough into a glamorous gemstone. In 2018, Tuzlukov flew from Thailand to Tucson, Arizona, to intricately shape the immense rough. Bridges hired videographers to record the entire month-long cutting process. According to Post, this is not often the case for a gem of this caliber. “Part of why we are so excited to get this stone is because it is one of the few gemstones where the whole process of going from a piece of rough to a cut stone has been really well documented,” Post said.
In 2020, Post and the rest of the Smithsonian’s gem-collection team examined Tuzlukov’s handy work up close during their annual visit to the Tucson Gem and Mineral Show. They began hearing whispers that Bruce Bridges was discreetly displaying an exquisite gem. “He showed it to us very secretly behind the curtain,” says Gabriela Farfan, the museum’s Coralyn W. Whitney Curator of Gems and Minerals. It surpassed all the hype they had heard. “I had never seen such a big tsavorite in my life—we were all just completely amazed by how beautiful and how large it was,” Farfan says.
According to Farfan, large tsavorites usually top out at the size of a pinky finger nail and weigh around 10 carats. Bridges’ tsavorite tipped the scale at 116.76 carats and was as wide as a silver dollar. It is more than 100 carats heavier than the National Gem Collection’s current largest tsavorite jewel.
Bruce Bridges named the stunning gem the Lion of Merelani, a nod to his father whose moniker in the region was "The Lion" and the area where it was discovered. He hopes it honors the outsized legacy of his late father in eastern Africa and the field of gemology.
In light of his family’s decades-long relationship with the Smithsonian, Bridges and SITR decided that the National Gem Collection would be the perfect home for the Lion of Merelani. “I feel my father would be overjoyed that one of the world’s finest examples of his discovery, Tsavorite, is being placed with an institution that his family has had such a close relationship with for over 55 years,” Bruce Bridges says. “This will allow his legacy to be shared with the world.”
Instead of being locked away in a private vault, the Lion of Merelani will be accessible at the museum. Like every other specimen in the collection, the record-breaking gem will remain available to researchers interested in exploring the intricacies of tsavorite crystals using non-destructive testing methods. “You never know what mysteries a gemstone can help solve,” Farfan says.
It will also remain on view for the millions of people who visit the museum each year. “When you see something like this, and you realize this came out of the planet, the Earth is suddenly a little more interesting,” Post says. “It's a more magical place.”
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