How diamonds are made
diamond.jaydip.me71 points by lemonberry 2 days ago
71 points by lemonberry 2 days ago
99% of all diamonds by mass are industrial diamonds. But they are so inexpensive that they only account for 3% or the revenue.
The jewelry is the remaining 0.8% by mass, and it is split roughly equally between the natural and synthetic stones by mass, but with about 80% of the revenue going to the natural stones.
Here is a very good video showing how large poly-crystalline industrial diamonds are made in the USA: https://www.youtube.com/watch?v=6o5RprIJmfA
China has their own, slightly different flavor of this machine, the cubic press. These machines are manufactured in thousands and cost about half a million USD each. They are used to produce both industrial and jewelry quality diamonds: https://www.youtube.com/shorts/cED0TjwKUDM https://www.youtube.com/watch?v=5cnEVb7aPfM
The original machine was invented by a guy at General Electric: https://en.wikipedia.org/wiki/Tracy_Hall
Since this is HN, as an aside, Surat (the city mentioned in the article where the gems are polished) holds the dubious record of being the last major city in the world to have had an epidemic of the bubonic plague[1] back in 1994. They took the opportunity to really clean up the place after that.
Today, Surat is known for another distinction: the world's largest office building[2] (even larger than the Pentagon).
true, I am the author of article. Surat's SMC does very good job keeping it clean.
De Beers built and has abandoned a very large CVD gem diamond synthesis in Oregon. This was their LightBox operation. They've transferred it to Element Six to rid the parent (De Beers) of the money sink, probably as a touch-up before a sale.
There was a fire sale of LightBox diamonds a few months back. I picked up 3 diamonds, all brilliant cut: 3ct. white, 2ct. pink, 2ct. blue. Total for the three was $600.
> From here, there are two rounds of sorting: gem quality and industrial grade. Most of mined diamonds never become jewellery. They go to cutting tools, drill bits, and grinding equipment.
For industrial use synthetic diamond is actually quite cheap now. The vast majority of industrial diamonds used today are synthetic and they've been affordable since the 1950s (?). Industrial-grade synthetic diamond grit or powder can cost as little as a few dollars per carat. This makes it far cheaper than mining natural diamonds for the same applications.
Diamond grit for polishing and grinding is now a cheap commodity. In 10,000 ct. lots, I pay from 5¢/ct. to 30¢/ct. depending on specific grit properties. I haven't searched for it, but diamond sandpaper should be a thing at these prices.
There was a discovery in 2024 on how to make diamonds under atmospheric pressure.
https://en.wikipedia.org/wiki/Synthetic_diamond#Crystallizat...
I thing that method can only produce small crystals, although I think the authors said something along the lines that it would probably be possible to further evolve the method to make them bigger.
Well, that goes for some diamonds.
There's another kind that are made by man. In recent years -- over the past four or five years -- there has been an explosion in synthetic diamond production, largely driven by factories in China and India. There are a lot of those factories (spurred by the relatively easy availability of the necessary production-line equipment) and they're all in cutthroat competition with each other, so there has been a race to the bottom on price.
You can get huge, very high-quality diamonds now for a fraction of what they used to cost. Like 95% off. It's crazy.
I'm often reminded of this classic tweet:
> it's actually crazy we figured out how to grow real diamonds that are cheaper and better quality than the real thing and so many people are still like, no thanks the suffering is what makes it special.
It's marketing plus perception of how expensive it is. Most of diamond purchases are for engagement rings. Nobody wants to appear cheap. The expense and rarity is the point.
> Most of diamond purchases are for engagement rings. Nobody wants to appear cheap. The expense and rarity is the point.
I relate to this. I wasn’t born rich and grew up poor. My parents started a business when I was in my teens, so I worked two jobs, and technically still do because I help them out. My parents instilled a work ethic in me that’s helped me get to where I am in life.
When it came time for me to buy an engagement ring, I went into the process knowing I wanted a natural diamond. My best friend said he could tell the difference between “real” and “fake” and that I shouldn’t be cheap. I didn’t want to be “cheap,” either. I was ready to spend $30,000+ on a diamond.
Instead, I bought a lab grown diamond. I spent $1,600 on a 1.72ct. My buddy thinks it’s real and nobody has even asked whether it’s lab grown or natural. I realized I was spending too much time asking, “why should I get a natural diamond?” The reasons never justified the cost. Spending 18x to 20x more on something that looks exactly the same and serves the same purpose just wasn’t logical to me.
That can be the right call (and is the one I would make) but for situations like this, it may be as much about how you think about something yourself rather than how others view it. If spending more makes it mean something different to you, then that can be a primary function. That being said, blood diamonds are a huge problem, DeBeers is a cartel, and we’d be better off investing our money in other ways that serve a relationship, family, etc.
It’s kind of surprising that diamonds still have appeal as jewelry at all given the rise of lab-grown. I always assumed that people liked them because they were rare and expensive.
Expensive because they were perceived as rare. Classic article: https://priceonomics.com/diamonds-are-bullshit/
Synthetic has pretty much eaten their lunch now.
That’s a silly way to look at it. Surely people can realize that something made through natural processes has more of an appeal than something made in a factory?
That said, most of the gems I’ve purchased in my life have been lab grown.
I'd argue that most people appear to prefer manufactured things these days.
No one's wearing clothes their mothers' spun because mothers' see that their children prefer the "higher quality" that is manufactured in factories.
Few choose to spend their time engaged in walking about in nature and choose instead to gaze endlessly at their factory built device that provides them content ground out in other sorts of factories. (content farms etc).
Something made in nature can be more appealing, but it seems to me that the modern preference is not at all for natural things. Hell, even in the diamonds we're talking about. No one's proposing with a natural diamond. People propose with carefully curated, carefully manipulated, and carefully presented diamonds. There's nothing natural about it, really.
Could you distinguish between them if you weren't told?
In final jewelry no. This is why brands like Tiffany are in panic and pivoting to mechanical-watch-like branding, where only inflated price matters.
With close microscopic examination of inclusions and defects, yes you probably can. There are also spectroscopic differences. In general looking at finished jewelry, no, not really.
> With close microscopic examination of inclusions and defects, yes you probably can.
With good laboratory instrumentation, you might be able to distinguish between them -- i.e. note that they're not perfectly identical, that they are distinguishable -- but, unless you are an expert, you would be unable to tell which of the two is the natural stone.
So, practically speaking, it doesn't matter.
Yes, you need to know which features are evidence of mined vs. synthetic/lab grown. Although there is equipment now preloaded with software that can discriminate. I think its based on photoluminescence.
De Beers sells devices that can distinguish between naturals and CVD synthetics. They're not cheap, but less than ~$80K, IIRC. They do a pretty good job, I've heard >90% success in identifying CVD stones.
There are some applications, such as IR optics, where natural diamonds aren't pure enough.
Links and examples? Last I checked, this applied to industrial diamonds, not jewelery.
My wife and I got our engagement and wedding rings from Krikawa[1]. The stones on her ring were synthetic, extremely affordable given the size, and visually flawless.
(Not quite as related, but the process was also really easy; we were able to communicate everything over email, get sizing kits mailed to us rather than having to go in person, and they sent us visual mock-ups and procedurally generated 3D videos of what the results would look like, which was helpful because the rings my wife picked out had been temporarily delisted as they found an issue with it that they wanted to fix, so they went ahead and figured it out so they could make them for us without us having to wait for them to appear on the site again).
Synthetic gem-quality diamonds are old news by now. Since the 2010s, you have been able to make essentially flawless diamonds by vacuum deposition, of higher quality than anything found in nature, weighing up to a hundred karats or so.
They’re also vastly more ethically produced than most natural diamonds, and don’t have prices inflated by the artificial scarcity imposed by the De Beers monopoly.
Monopoly? DeBeers itself is virtually worthless now, its parent Anglo American can’t even sell it at a huge discount.
https://www.forbes.com/sites/timtreadgold/2026/02/22/diamond...
Try somewhere like Blue Nile [1]. The price of natural diamonds increases exponential once you go over 1ct and the size becomes rarer.
Here's a quick comparison on just size, clarity and the visibility of inclusions.
A 1ct very good quality stone, E-F, VVS2 or better, no fluorescence - you're looking at a 88% reduction in cost ($700 vs $6,000).
Jump to 2ct and it's $2,300 vs $32,000.
At 3ct, the lab grown is still only $4,200 where the natural at that size starts at $82,000.
And in China and India they're roughly 3x cheaper than that, i.e. a 3ct lab-grown stone is somewhere under $1500. (I posted a link to one absolutely typical example in a previous comment.)
It's amusing that the price of gold has skyrocketed just as the price of diamonds has nosedived. Some old rings, which were valued for the small diamonds they carried, are now more valuable for their weight in gold.
How large do you want them?
> https://item.taobao.com/item.htm?id=828627288905&skuId=55567...
This ring goes up to 5ct, and some other listings are at 7ct.
A 3ct example at the link, which would easily be a >$20k ring under other circumstances and isn't too comically large, will run you about $1500.
There are many, many others.
James Allen, Brilliant Earth, Jared, Blue Nile, all of these vendors sell lab created diamonds openly and let you compare side by side. A diamond that’s $10k natural can be had for $1500 lab created without any scarcity.
>"You can get huge, very high-quality diamonds now for a fraction of what they used to cost. Like 95% off. It's crazy."
The thing is though, what's the point? Unless you're trying to actually pass your diamond as real, there's literally no difference between that $1500 lab grown gem and a $5 piece of costume jewelry. No one but a jewler will ever tell the difference, so why pay anything at all? With real diamonds today you are paying for that certificate of providence, which is what actually gives it any value. Used diamonds of course are worth nowhere near their retail value, but used lab grown are worth zero, both monetarily and sentimentally. Grandma's heirloom Tiffany engagement ring will have meaning in the way that a lab grown no name ring ordered online will not, even if they are completely indistinguishable.
As a fan of cool rocks and gems, and putting aside price and societal influences, diamonds are cool!
Especially compared to hard plastic “costume jewelry” (which I think you’re referring to), gems are hard, don’t scratch as easily as hard plastics, and have cool reflections.
Referring to mossanite and cubic zirconia, which are completely indistinguishable to a normal person, and can be had for dollars per carat.
> Grandma's heirloom Tiffany engagement ring will have meaning in the way that a lab grown no name ring ordered online will not, even if they are completely indistinguishable.
Not sure how to parse that. Perhaps it's a cultural thing? This seems to be conflating value, meaning and worth in a confusing-to-me way.
- "Grandma's heirloom" would have sentimental value, regardless of brand name, production process or monetary value. Grandma's candy box or her modest music box would have similar sentimental value. Depending on what this grandmother meant to you as a person, this could be positive or negative sentimental value.
-"Tiffany's" versus "no name, ordered online" might for equal quality jewelry make for a slight higher resale value. All other things being equal, that is.
- Lab grown versus mined could make a slight difference in resale value. This is very often very much overestimated because of how the diamond retail market works.
- Lab grown versus mined really depends when it comes to emotional value.
- For example, if someone were to offer my wife or me a mined diamond with no history, we'd assign it negative emotional value because of the suffering attached. Unless it were to have come from a historical source with no money having changed hands, not even in the second hand trade. In which case no extra harm would have been done even by trading in the secondary market.
- Others might attach positive emotional value to the rarity of the mined diamond.
- Some sociopaths, psychopaths or sadists no doubt attach positive emotional value to the knowledge people had to suffer for the ring on their finger.Was hoping for a walkthrough on how chemical vapour deposition (cvd) works. That stuff is fascinating, and it's how most diamonds are (man-)made
I wish articles/domains like this one, which are accessible, playful, informative, short, and with images would be easy to identify in HN.
That would be something worthwhile to share with children aged 8-12 who love learning new things.
Playful yes, but it is anything but accessible.
hello, I'm the author of article. I've tried my best to use accessibility patterns. If there's anything that i can improve lmk :)
For my two cents, the jiggly images are distracting from the text and the site makes my (admittedly somewhat old) phone stutter when scrolling. Overall it feels like you tried doing too much with it when simpler would have been better.
Anyone know how those MS-paint-like vibrating gifs were made?
it's made with "WigglyPaint" (https://beyondloom.com/tools/wigglypaint.html#main).
That's not how Superman did it.
Amazing design. Very interactive!!