Testing the Hope Diamond
Scientists at the Natural History Museum search for the elusive "recipe" that endows the famed gem with its unique blue color
- By Joseph Caputo
- Smithsonian magazine, November 2010, Subscribe
At first, Evalyn Walsh McLean, an heiress living in Washington, D.C., didn’t want to buy the Hope Diamond. She was unhappy with the setting surrounding the precious blue stone that had once belonged to King Louis XIV and asked jeweler Pierre Cartier to create a new one: a circle of 16 clear diamonds, shaped like squares and pears.
That was in 1910, and for much of the past century the Hope Diamond remained in its Cartier setting. But several months ago, it was taken from the National Museum of Natural History’s gem hall for an overnight stay in the mineralogy lab. There, geologists conducted an experiment to learn precisely why the Hope Diamond is so blue. Every gem has its own unique molecular formula, which is determined by how its atoms bond together in the extreme heat of the planet’s crust. But the formula for deep ocean blue is rare, occurring in only one out of every several hundred thousand diamonds. At 45.52 carats, the Hope, discovered in 17th-century India, is the largest-known deep blue diamond. “Its creation, as far as we know, is a completely unique event in the history of the earth,” says geologist Jeffrey Post, a curator at Natural History.
But before the experiment could begin, some delicate surgery had to be performed to remove the blue diamond from its setting. At 9:16 p.m in a room almost as long as a bus, where fluorescent lights and white walls canceled out even the sparkle of topaz on the shelves, jeweler Stephen Clarke donned a pair of glasses equipped with magnifying lenses and reached for his tools. He steadied the walnut-size gem in his left hand—his fingerprints smearing its 60 facets—while his right hand wielded a pair of tweezers. “It’s like a little puzzle,” Clark said, as he unhooked the small wire rivets holding the diamond in place.
A security officer peeked into the room. “Look at that,” he said. “It’s even more beautiful out of the setting than in.”
At 12:35 a.m., two researchers wearing blue gloves cleaned the stone of the jeweler’s prints. Carefully, they loaded it into a custom-made mount and placed it into the chamber of a device that would fire an ion beam, boring a ten-angstrom-deep hole (just over four-billionths of an inch) into the gem.
“Looks more like a science experiment than a fancy gemstone right now, doesn’t it?” Post said to a film crew from the Smithsonian Channel, which will air a documentary on the Hope Diamond on November 21.
It would be another hour before the experiment could begin, since all the air first had to be pumped out of the chamber to create a vacuum. The scientists rested their eyes. “This is our one shot,” Post said. “We’ll take measurements until they tell us the diamond has to be put back on display.”
While the precise recipe for the Hope is a mystery, geologists know that the primary ingredient endowing the diamond with its color is the element boron. The night’s research may someday be applied to making synthetic blue diamonds—not only for jewelry, but for electronics. Boron allows current to pass through the stones more efficiently than your average semiconductor. “It’s not clear yet how we’re going to be able to make these things,” Post said, “but the experiment gives us a way of seeing how nature did it.”
At 2:35 a.m., with the click of a computer mouse, the ion beam fired. Millions of Hope Diamond atoms sputtered into the vacuum. They were sucked into a tube, past a detector that analyzed the elements.
The initial results came in. Colored spikes appeared on a computer screen, announcing the presence of boron, carbon, hydrogen and possibly some nitrogen. Based on the findings so far, the concentration of boron varies within the diamond, ranging from zero to eight parts per million. The Hope is actually a mosaic of blues.
It will be months before the scientists publish the full results of their experiment. In the meantime, the Hope is back in its display case and—unknown to most museum visitors—a few million atoms lighter.
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Comments (18)
Wow! that sound.....amazing! i think the Hope Diamond is beautiful! i remember i could hardely catch my breath when i saw it for the first time cause when i was in its presence everything felt.............MAGICAL! I 3> HOPE DIAMOND
Posted by bella shallenberger on January 10,2013 | 08:30 PM
Looks to me they needed an excuse to make the diamond smaller. I hate they are making or already have made a new look. The man who donated it left it as he received it and donated it. I believe it should stay in its original form they received it. When I was 10 yrs old that's the way I saw it. So what are they doing with the pieces they cut off? They made a bad judgement!!!!
Posted by cyndi on December 13,2012 | 01:43 PM
It is 2012. When are we going to get the results and significance of the analysis? Or did you just waste time money and effort for nothing? You said it will be months. But now it has been years.
Posted by Jen on March 13,2012 | 07:44 PM
All through high school I wished that I had the power to write a nice long paper about virtually nothing. A rare diamond was analyzed with a cool device? Profound. Now it is almost May of 2011. Wouldn't it be far more interesting to write about the results and significance of the analysis?
Posted by Robert on April 25,2011 | 10:10 AM
I read your article awhile back and just the other day watched the special program on the Smithsonian channel. It was very fascinating!
I knew nothing of the history of its past ownership and the surrounding rumors of its curse.
The science of the blue diamond is interesting, but the stories of its history are just as interesting...if not more so.
Thanks for bringing us such a wonderful well done special program!
Posted by Kathy K. on December 29,2010 | 11:54 AM
Just to add some sense of scale for those concerned about the "hole" in the diamond. 10 Angstroms is one ten-millionth of a centimeter. The diamond itself is about 2.5 centimeters in diameter. If the diamond were expanded to be the size of the earth (a factor of about 500 million), the "hole" would only be about 50 cm, or less than 2 feet deep. Alternatively, the smallest object visible to the human eye is about 1/100th of a cm. For the depth of this "hole" to be just barely visible, the diamond would have expand to 100,000 times larger than it is...well over a mile in diameter.
Posted by Adam Trotter on December 27,2010 | 04:36 PM
Hello,
I missed the special on the Hope Diamond and was wondering if you plan on showing it again in the near future?
Thank You,
Carl
Posted by Carl on December 4,2010 | 03:53 PM
I was fascinated by the article in Smithsonian magazine on the Hope Diamond, but I was not able to watch the program yesterday. Will it be rebroadcast on the Smithsonian channel or on PBS? How can we find out when that might be?
Also, the loss of some atoms for a good cause, which loss is imperceptible to the human eye should not be shocking. By contributing to furthering scientific investigation and possible worth while application, the Hope Diamond is earning its keep.
Posted by Dorothy Howells on November 22,2010 | 12:07 AM
There isn't a hole in it. They said in the article the atoms came from the surface of the stone.
Posted by Amber on November 12,2010 | 12:01 AM
To those concerned about the "hole" in the diamond:
Do you realize how small 4 billionths of an inch is? The "hole" is NOT visible to the naked eye, and would require EXTREMELY powerful magnification to even notice it. I think using the word "hole" was a very poor choice on the writer's part...trust me, it is not that big of a deal.
Posted by Christa Jackson on November 11,2010 | 07:26 PM
I understand that drilling a hole in the diamond sounds devastating but not when you understand the actual size they are discussing. a ten angstrom deep hole is still 8,000 times smaller than a single human blood cell which measures an average 80,000 angstroms. this small hole isn't even visible to the naked eye. you need a microscope just to see a single blood cell and then you need to go 8,000 times smaller just to notice the hole. It really isn't going to affect the beauty of the stone in any way.
Posted by Michael DeMeritt on November 11,2010 | 06:08 PM
Where can be found the secret mystery of that hope diamond? Can the origen of that; be white brilliant stars at (by) dak blue sky during the without clouds at just before some open evenings on the sea sides?
And my request; can be not opening the micro holes for enter or enterferring into the moleculaire cristhalised structures.
The dia-monds are diameteral and they belong to dai-monds. The permissions of owners of World might be obliged for their operations. Valor Alexander
Posted by Valor Alexander (Değer İskender) on November 9,2010 | 01:12 PM
it was a beautiful Diamond, it made me mad because of what they did to it
Posted by Ms.Williams on November 8,2010 | 08:29 PM
FYI the Smithsonian Channel is on 565 on DirecTV. It is a HD channel and it may only be available in HD.
Posted by Mike on November 4,2010 | 08:01 PM
Why would anyone with a sane mind would put a hole in such a rare gem. I saw the diamond in 2009 and was shocked at the size and beauty of it. What you have done is really shocking to me.
Posted by Patricia Thomas on November 4,2010 | 02:30 PM
I've always loved this diamond and my family has always loved seeing it at the museum. But knowing there is a hole in it, albeit a very very small hole, just doesn't sit well with me.
Posted by Renay on October 30,2010 | 04:22 AM
I am a retired diamontologist. When I was in D.C. For my sons graduation there was little time for site seeing but I had to see the "blue" while I was there. I look forward to seeing the special on the diamond in November.
Posted by Carla Cottrelln on October 23,2010 | 11:59 PM
Your article is very interesting and I would love to view the Nov 21 documentary. I live in S FL and have DirecTV. Can you advise me as to how I can find the "Smithsonian Channel?"
Thanking you in advance
MaryMae.................. mbflsunflower@aol.com
Posted by MaryMae on October 22,2010 | 02:34 PM