Even Jack Dorsey's rebranded crypto company is getting in on the craze for tungsten cubes, the super-heavy metal blocks that cost up to $3,500

• Square's rebranding announcement as Block contained a strange reference to tungsten cubes.
• The mention was a signal to crypto enthusiasts, who were recently in a frenzy to buy the novelty objects.

In its rebranding announcement as Block, the digital financial company Square contained an odd reference.

"Not to get all meta on you… but we're going to!" the company tweeted. "Block references the neighborhood blocks where we find our sellers, a blockchain, block parties full of music, obstacles to overcome, a section of code, building blocks, and of course, tungsten cubes."

Last October, tungsten cubes were thrust into the national spotlight after a few viral tweets inspired a quasi-obsessive fixation among crypto enthusiasts with the unique tactile experience of the objects — and their extraordinary weight-to-size ratio.

Most of the cubes were sold by a small industrial manufacturer outside Chicago, Midwest Tungsten Service.

MTS had seen sales spikes before and would occasionally experience a flutter of activity after a science blog or YouTube video featured one of its metallic novelty cubes, spheres, or fidget spinners.

But the surge in the second half of October was like nothing they had dealt with before, MTS ecommerce director Sean Murray told Insider.

"By the third day, it was like, 'Oh, wow, this is completely different,'" he said.

Tungsten is a high-density metal — comparable to gold — that is used in a wide array of industrial applications. Even small volumes of the element are strangely heavy, with 1.5-inch cubes weighing 2.2 pounds ($199), or 3-inch cubes at 17.6 pounds ($1,599).

"We actually had what we thought at the time was multiple years worth of inventory of some of those different sizes," Murray said.

On October 13, cube sales spiked 300% and Coindesk jumped on the story, followed by Bloomberg, Vice, and The Wall Street Journal.

Nic Carter, a VC and an early cube collector, told the Journal that the cube's density offered a pleasing sensory contrast to the intangibility of digital currency.

"We're just deprived of physical totems of our affection, and so tungsten fills that hole in our hearts," Carter said.

One thing that differentiated the crypto crowd from previous buyers was the greater share of interest in the larger cube sizes.

"We thought nobody would buy our 17.6 lb, 3-inch tungsten cube. We were so, so wrong," the company says on its Amazon listing for a new 4-inch, 41.6-pound cube ($3,499).

Murray said the company was surprised by the sudden interest, but well prepared to make the most of it, since they tend to carry more inventory than other "just-in-time" manufacturers and had a well-established, rapid-order-fulfillment process.

"We had people who normally come in at 6:30 a.m. coming in at 1:30 a.m.," he said."We had spouses and children of people come in to help out at various times."

In addition to traditional ecommerce responses like pulling staff from other areas of the company to help process orders or dealing with Amazon's fulfillment network, Murray said he also underwent a crash-course in crypto.

"I'm just someone who, if there's a new thing, I like to check it out," he said.

MTS began accepting bitcoin payments on its website, and on October 22 announced it was auctioning an NFT for the largest Tungsten cube ever, measuring 14.5 inches and weighing in at a whopping 2,000 pounds.

Due to the sheer logistical difficulty of shipping an item with those specs, the cube will remain at MTS' facilities where its owners can schedule one visit per year to touch and photograph it. The winner was a crypto group known as TungstenDAO that paid nearly 57 ETH (worth about $247,000 at the time).

Murray said the crypto-fueled peak has passed, but that holiday sales are starting to pick up as customers shop for stocking stuffers. He also said that bulk orders are starting to pick up from companies that want engraved cubes to give to employees.

"In this case, cryptocurrency-related firms are a large part of it," Murray said.