Vodka filtered through actual diamonds is the most luxurious vodka in the world. This much is obvious. The process involves diamonds, which are the most luxurious gems in the world, so, of course, this vodka will be the most luxurious. I didn’t invent logic. I just apply it. And you don’t have to take my word for it—just look at the ads and marketing material for these ultra-deluxe spirits.
Three Sixty Vodka made in Germany is “diamond-filtrated” through diamond crystal dust, a process that results in “tasteful exclusivity.” Diamond Glacier 33 ($30) is filtered not once, not twice, but eight times through diamonds, yielding “a remarkably smooth and clean vodka that has to be experienced to be fully appreciated.”
Perhaps, the best-known vodka to tout its dalliance with gems is “multi-award winning, ultra-premium Crystal Head Vodka,” sold in skull-shaped bottles by actor Dan Aykroyd, which costs $50 and is “filtered seven times, of which three are through layers of semi-precious crystals known as Herkimer diamonds.” (“Herkimer diamonds” sound exotic unless you’ve passed the Herkimer exit on the New York State Thruway. It’s basically quartz crystals from upstate New York. There shall be no further discussion of “Herkimer diamonds.”)
And I recently learned about Carbonadi ($70), made from Italian wheat, distilled five times and then “passed through a distinctly rare filtration process utilizing carbonados, also known as ‘Black Diamonds,’ which are the toughest and rarest form of natural diamonds.”
I’ve been more housebound than not lately, like everyone else in the pandemic age. As such, I’ve had time on my hands. Marooned in a world where the clock appears to be perpetually set at 3:15, I felt a need to resolve a question: if diamonds are the hardest objects ever found in nature and are impervious to just about everything, how can they possibly serve as an effective filter? A filter, after all, by its very definition, needs to be porous to entrap impurities. Again, I didn’t invent logic…
Rabbit, meet hole.
After some extended burrowing, exploring one shadowy chamber after another, I emerged into a glittery world of science, drinking and meteorites. And I finally came up with a few answers about diamond filtration, including some I didn’t quite expect.
Let’s start with history. Filtration has long been a vital part of making vodka. “In the history of Russian distilling, filtration through charcoal occupies a special place,” writes William Pokhlyobkin in his comprehensive 1991 book, A History of Vodka. In the 19th century, distillers experimented with all types of wood to see what was most absorbent. They used beech, oak, alder and birch. They used heartwood, dark wood, trees that had knots cut out and trees no older than 40-years-old.
Over time, the favored wood became birch, which was abundant and effective at entrapping elements distillers wanted entrapped. They discovered other filtration truths: that diluting a spirit to a low proof resulted in more impurities being captured than working with high-proof distillate. They learned about activated charcoal, which is made using hot gasses and results in a more porous, more absorbent form of carbon. “The spirit was thus refined to virtual purity, even when it was impossible to detect any trace of aldehydes [a class of organic compounds that include some off-flavors] even by an ultra-sensitive test,” Pokhlyobkin wrote.
When vodka made the leap from the old world to the new in the post World War II-era, claims of filtration traveled with it and many brands advertised their proprietary charcoal filtration process. In 1958, to give one example, Samovar Vodka trumpeted that it was “extra-filtered… through the world’s finest charcoal.”
Of course, the world’s finest charcoal are actually diamonds. Both charcoal and diamond are essentially the same thing—pure carbon—although one has been compressed into crystalline purity at an unfathomable pressure miles below the Earth’s surface.
The first reference I can find to diamond-filtration is from 1966. Old Timer Vodka was advertised “our best diamond filtered” and was available for $4 a quart, suggesting the claim might have been hyperbolic. References to diamonds surged in the 1990s, notably by Rain Vodka ($15), made by the Sazerac Co., which advertised itself as being filtered through diamond dust. Then came the gem-encrusted 2000s, when brands claiming to be filtered through diamonds soared.
While charcoal and diamonds are essentially both pure carbon, they vary greatly in how those carbon molecules are arranged. Charcoal has an open molecular structure, which can be made even more open, and thus more porous, by activating it.
Diamonds on the other hand, are tightly packed molecules. Think of two piles of firewood. One is dumped on a lawn by a dump truck. The other is stacked by someone with too much time and a bad case of OCD. The second pile is a diamond.
Let’s continue on in relatively simple terms, consider that there are two forms of filtration. One is mechanical, which sorts out suspended solids up to a certain size—think of a paper coffee filter. The other is chemical filtration. Owing to bonds and valances and other such things that trigger PTSD from high school chemistry class, some elements naturally attract and bond with other elements. Think of soap and grease—soap attracts and binds with the grease, so the bacon fat decides it would rather go hang out with soap than linger on your nasty breakfast plate.
Know what else is attracted to grease, strangely enough? Diamonds. Diamonds are hydrophilic, meaning they repel water, but they bond with elements found in grease. In fact, some forms of diamond mining involve belts or tables coated with grease, to which diamonds adhere but other minerals do not.
The words “grease” can be traced back to the Latin word for “fat.” And fats are basically large molecules made up of carbon, hydrogen and oxygen. Some of these fatty compounds are produced during the fermentation process, notably fatty acids, which can add sour notes, among others. In some spirits this is desirable, especially since these compounds can convert into something delectable while aging in a barrel. In vodka—which is prized for its purity—not so much.
So can diamonds capture some of those impurities and prevent them from going into the bottle?
Well, yes and no, says, Stephen Haggerty, distinguished research professor of geophysics at Florida International University. He says it depends on when in the process the filtration is carried out.
“Here’s the thing,” he told me. “If the filtration is carried out prior to distillation, then all of these non-essential alcohol components—all the oily components—would stick to the diamonds.” For various reasons, it wouldn’t be as effective after distillation “unless it’s done just above the vapor pressure point,” he says. (Insert “shrug” emoji here; I missed that chemistry class.) Pre-distillation filtering would, however, involve about ten times as much liquid, and be far messier, as the solids haven’t yet been distilled out. So as far as I know, nobody does that.
And what about the so-called “black diamonds?” Carbonado diamonds, which are used in the filtration process of Carbonadi Vodka, are actually diamonds, says Haggerty, who wrote in an academic paper that these are “the most enigmatic of all diamonds.”
Carbonado is only found in two regions of the world—the Central African Republic and Brazil—and current thinking is that these were created during a catastrophic meteor strike on Earth eons ago, even before the African and South American lands masses had pulled away from one another.
Not only are these diamonds opaque and black, but are structurally unique as well. Think of a wood pile that is neatly stacked but with a bit of space between the logs. “The difference is that it’s five to 15 percent less dense than diamonds, and that’s directly related to the pores in it, and that affects its porosity,” he says. This, in turn, increases the surface area and allows more opportunity for the diamonds to bond and sequester impurities.
Ricky Miller III, the co-founder and creative director of Carbonadi Vodka, says they looked into this process because one of his former partners had family in the diamond business. Through testing various gems they came across carbonados and their vaunted porosity. “We thought it was a super sexy process,” he says.
The Carbonadi process involves packing 3,000 carats of raw black diamonds into a tube (Haggerty says these can be bought for as little as $2 per carat), and through this they run a wheat-based distillate imported from Italy several times at high pressure. The diamonds are small and rough, he says. “Think Fruity Pebbles, or about the size of a large Rice Krispy.”
What impurities are being cordoned and captured? “I would be lying to you if I said I knew exactly what was being pulled out,” Miller said. “But it picks up and absorbs impurities that aren’t caught in a conventional process.” He insists that you can taste the difference. To sway skeptics, he’s working on a portable diamond filtration device to bring to bars and trade shows for before and after tastings.
So, yes, diamonds in theory can remove impurities. Although in practice—filtering after distillation rather than before—may not be the most effective.
But does it matter? The craft in vodka is in the marketing, not the production. And the modern super-premium vodka industry has been built on the perception of purity and exclusivity—which makes pairing them with diamonds a natural.
Bottom line: Does vodka filtered through diamonds taste better? Maybe.
Is it more luxurious? Obviously. That’s just plain logic.