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Cool jewels — these necklaces help the wearer beat the heat

The Nano-Ice Cooling Necklace.Taryn Gangi

Sam White developed a reliable technology to help 25,000 dairy farmers in India keep their milk cool. So, he figured, how hard could it be to help his wife keep cool, too?

White is an entrepreneur who cofounded Greentown Labs Inc., the incubator space for clean energy startups in Somerville, and then moved to India, where his company, Promethean Power Systems Inc., developed an innovative refrigeration system.

While living in India for three years, White’s wife suffered from the “unbearable” heat in Mumbai, he said. It inspired him to create a personal cooling system based on refrigeration technology that White packaged in jewelry — a kind of necklace of ice cubes.


The Nano-Ice Cooling Necklace uses plastic orbs filled with a proprietary liquid that White said produces longer-lasting ice than plain water.

“It’s amazing, it feels like ice around your neck,” said Lea Grossman, a 72-year-old Brookline resident who bought White’s necklace when she met him at her local farmers market two years ago. “It’s not too much, and the moment you feel cooler, just take it off!”

A Kickstarter campaign in 2015 raised more than $15,000, and White now makes the necklaces in Ipswich and sells them for $49. He expected the necklaces would be a work accessory, especially for janitors or chefs who work in uncomfortable environments. But comments on his Kickstarter campaign suggested a bigger audience: women going through menopause and patients with multiple sclerosis or cancer.

“Heat is the kryptonite for any autoimmune system, so that’s why this necklace works so well,” he said.

His invention is similar to a cooling necklace developed in 2011 by a New York woman that is a more fashionable take on the same idea.

The “pearls” in the Hot Girls Pearls necklace are made of the same plastic used in motorcycle helmets and filled with nontoxic gel commonly found in ice packs. Weighing about 6 ounces, they sell for $70 to $90.


“When I saw it for the first time, I laughed really hard,” said Hot Girls Pearls founder Constance Sherman, who has since moved to Florida. “And then I ordered one for me, and one for my patent attorney.”

After first wishing White’s invention would “die a natural ugly death,” Sherman cooled off and realized the market is big enough for both types, she said. Her product is decidedly aimed at women, while the bulkier one from White is a unisex model. Sherman’s necklace provides about one hour of cooling, White’s about two.

Hot Girls Pearls. Robert Farber

“In fact, we do have two different finished products, and different audiences, as well. The most important thing is that if we help people feel more comfortable in their skin, there’s room for both,” he said.

Sherman was inspired to make the necklace when medicine she took after a surgery made her feel like an “inferno.”

“I made something that’s beautiful and wearable, and I’ve sold well over 100,000 pieces,” Sherman said.

White got the idea for the necklace when he was working with Olin College, the engineering school in Needham, to help dairy farmers in India, where diesel generators to power cooling equipment are expensive. The proprietary liquid helped to substantially increase how much milk could be cooled with the refrigeration systems Promethean Power developed for rural farming villages.

Watching his wife struggle with the heat at home, White wrapped his plastic orbs in cloth, and froze them.


“She came up to me the next day and said the cooling effect lasted for hours. She loved it,” he said. “And so I immediately thought I have to share this.”

A necklace soon emerged as the most practical way to package the cooling technology for everyday use. While the plastic orbs are dressed up in brightly colored cloth, White’s Nano-Ice necklace isn’t designed to look like evening wear.

“Mine targets more of a utilitarian technology rather than something quaint and beautiful,” White said. “The core of this is the technology, and secondarily aesthetic.”

Plus, he added, “beauty is always in the eye of the beholder.”

Natasha Mascarenhas
can be reached at natasha.mascarenhas