Scientific gems are having a sparkly moment

Jul 11, 2023

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Way back in 2013, at a mobile phone industry conference, a representative of a New Hampshire-based company called GT Advanced Technologies whipped out a chunk of concrete he found in the parking lot and scraped it ferociously across the screen of his modified iPhone. He was giving a demonstration to a reporter.

"I’m gonna start to scratch away and when I clear that away, you’ll see that there's no damage to the screen itself," he said. "You can't scratch sapphire. The only thing that's harder than sapphire is diamond."

GTAT had agreed to make sapphire display covers for Apple, which was considering replacing the Gorilla Glass on its screens with the much harder crystalline material.

"Apple basically fronted them hundreds of millions of dollars to build a factory in Arizona," explained Bob Sanders, a reporter at the New Hampshire Business Review who covered GTAT for more than a decade.

GTAT would not just have to make any sapphires, but huge ones, weighing hundreds of pounds – much larger and purer than what's found in nature.

"And they signed a contract to do this. The problem is they couldn't," Sanders said.

They hadn't made sapphires before, just the furnaces used to make them. There were defects, there were cracks, and the enormous crystals, called boules, were useless. They piled up in what employees called "a boule graveyard," said Sanders.

You may have noticed that your iPhone is not made with sapphire today (though the camera lens cover is). GTAT went bankrupt. Shareholders said that they lost more than $1 billion. Litigation ensued. The giant sapphires disappeared.

"We were asking around pretty actively to see if any of it had gotten out during the bankruptcy," said Stephen Challener, co-founder of Angry Turtle Jewelry, based in Raleigh North Carolina.

"We were lucky enough to find one from a surplus warehouse somewhere in Oregon i think. And we had it shipped to us freight," he said.

The boule weighed 500 pounds.

"And we had to take it apart with a concrete saw with sledgehammers to get out the few clean areas. But once it's trimmed up it cuts absolutely beautiful stones."

They glitter and shine and Challener sells them along with many other synthetic stones on Etsy and Instagram.

"Our business is centered around repurposing industrial materials which are grown for science, medicine, and research and using them as gemstones," he explained.

They range from a few dollars to a few thousand dollars for a single stone. In his workshop, Challener holds a pink ruby larger than a golf ball and slices through it with a diamond saw. His fingers seem perilously close to the blade. "This may look hazardous but this type of smooth-edged diamond blade is much better at cutting through hard things than soft things – so while it goes through ruby it can't easily cut my skin," he said.

According to Challener the ruby is left over from the 1980's Strategic Defense Initiative, also known as the Star Wars Program.

The crystals he uses were originally intended for lasers, components in medical imaging machines like PET scans and digital x-ray machines, cellphones, fiber networks, and even fusion reactors.

"Sourcing this stuff is basically a full-time job, we have to do a lot of cold calls send a lot of emails and find crystal growers or processors or researchers who are willing to part with their scrap."

They are not always willing. Sometimes the crystals’ composition is top secret. Sometimes producers prefer to melt their scrap and recycle it. This type of highly specialized material isn't exactly easy to make.

"You have to have a chamber, a high-temperature crystal growth oven that can melt the mineral constituents of that particular crystal up at around 4,000 Fahrenheit," said Zack Cole, director of Scientific Materials, a group within conglomerate Teledyne, which makes crystals for lasers and also for quantum memory experiments.

Just to hold the molten lava-type melt in which the crystals grow, they use containers made of exotic iridium or molybdenum – materials that will heat with induction but won't melt themselves.

The air temperature in just the room, let alone the furnace, has to be controlled to within less than a degree to prevent defects.

"If the air temperature fluctuates beyond that level or fluctuates very fast, the crystal will respond to it and our control systems controlling the crystal will have to respond to that," said Cole.

Crystals begin with a seed and grow over the course of days or weeks.

Some of the scientific crystals Challener cuts contain rare earth elements, some of them change color, some have colors that would never be found in nature, and some of them actually glow in the dark (after charging with light – they’re not radioactive).

"I think my favorite is LuAG – lutetium aluminum garnet, it is used as a scintillator in PET scanners to detect invisible radiation and it has an insane neon green color it glows like nobody's business," said Challener.

One of the first people to get a fluorescent LuAG from Challener was Eric Bardawil, who runs House of Sylas and specializes in cutting large gems. (He has a guide to lab grown gems here.)

"He sent it to me, I opened the box, it's glowing. I texted him this stuff is it safe are you gonna kill me if I cut it?" Bardawil said. He cut it, posted the video on Tiktok and it got 1.2 million views.

"People went crazy and then for the next month I think all I did was sell LuAG gemstones," he said.

They go for a few hundred to more than a thousand dollars. Bardawil thinks the popularity of these industrial stones is in part because of a shift in the diamond market. People are gradually warming up to lab-grown diamonds for wedding rings, and that's spilled over into acceptance for synthetic colored stones – especially if they have a good back story like failed industrial products or fusion generator parts.

"We’ll have to kind of see whether it fizzles out or what," he says, "but I have faith!"

For now, the crystals are a-glowing, and so are sales.

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