this post was submitted on 10 Jun 2026
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Today I Learned

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[–] mineralfellow@lemmy.world 17 points 3 days ago (3 children)

Seems to be a lack of mineralogists here.

Gemstone is a market term. There is no division scientifically between a gem and a mineral.

Minerals form in specific geological settings as a result of temperature, pressure, and the composition of the materials reacting. On the surface of the Earth, we tend to mostly have low temperatures and low pressures. Most minerals are made of only 8 elements, one of which is carbon.

“Gemstone quality” is based on whether or not a mineral can be attractive when faceted. Most minerals do not pass this aesthetic.

To say that a mineral is common or rare is extremely dependent on context. Garnet, for instance, could be the gem that is targeted, or could be waste material that is an annoyance. Most diamond mines throw away massive amounts of garnet.

So, the statement in the title needs a lot of caveats.

[–] SpecialSetOfSieves@lemmy.world 1 points 13 hours ago

Thanks for this post. People don't understand about geology and context, I find. I would love to see more of your commentary in the Perseverance rover and Curiosity rover communities, although I do remember seeing you there in the past. My mineralogy is still rather basic, all told, and with the exotic lithologies Perseverance is uncovering (well, by Martian standards - granite and serpentine, yet!), your participation would be most welcome.

[–] titanicx@lemmy.zip 1 points 1 day ago

That's a facetted statement.

[–] Sp00kyB00k@lemmy.world 2 points 2 days ago

Looked up garnet, that's really pretty.

[–] Th4tGuyII@fedia.io 66 points 4 days ago (1 children)

All you actually need to make a diamond is extremely high pressure and carbon, which are both in relative abundance below the Earth's surface.

So compared to other gemstones that require specific multi-elememt minerals to form, on top of any other conditions, diamonds being the most common makes complete sense.

Which makes DeBeer's whole campaign of artificial scarcity only that much worse.

Edit: Not Dabares haha

[–] crystalmerchant@lemmy.world 38 points 3 days ago (2 children)

Feel like this is common knowledge by now right? Diamonds are scarce because DeBeers controls the supply to keep prices high. Not because they're geologically rare

[–] chuckleslord@lemmy.world 19 points 3 days ago

Well, yes, but also no. Even without DeBeers fuckery, they'd still be worth more than other gems. Diamonds are incredibly common, but large, high quality diamonds are both rare and difficult to process without damaging. Diamonds are brittle as fuck.

The analogy I use is imagine if the latest home decor trend was perfectly preserved tree stumps. Everything intact, from the tiniest root all the way to the trunk. Super common, yeah, but it would be enormously expensive to have done.

[–] SaveTheTuaHawk@lemmy.ca 3 points 2 days ago

Ad ad campaigns convincing women love is about a massively overpriced chip of stone.

[–] Goldholz@lemmy.blahaj.zone 47 points 4 days ago (4 children)

Yep. And basicly all coloured jems are saphires

[–] flamingo_pinyata@sopuli.xyz 26 points 4 days ago (5 children)

Sapphires are awesome and easy to produce

[–] Goldholz@lemmy.blahaj.zone 17 points 4 days ago (1 children)

Really? The jewler and goldsmith told me opposite

[–] flamingo_pinyata@sopuli.xyz 44 points 4 days ago (2 children)

Not sure from jeweler perspective, they might be hard to put into jewelry.
But synthetic sapphire is relatively easy to produce, enough that it's used for watch faces.

https://en.wikipedia.org/wiki/Sapphire#/media/File:Sapphire_boule,_Kyropoulos_method.jpg

[–] PineRune@lemmy.world 20 points 4 days ago

I'm wearing a watch with a sapphire lens right now! From what I understand, the tradeoff between different watch faces are how easy/hard they are to scratch vs shatter, with sapphire being the most scratch proof and a plastic polymer (I don't remember which) being the most shatter resistant.

[–] kernelle@lemmy.dbzer0.com 4 points 3 days ago (1 children)

They also use them in high-end watches as tiny bearings for the movements IIRC

[–] Dultas@lemmy.world 2 points 3 days ago* (last edited 3 days ago)

Correct, if a watch says 17 or 21 jewels that's what they're referring to. Although unlike the lens they're typically a reddish color.

*The red is from them being ruby not sapphire.

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[–] wonderingwanderer@sopuli.xyz 6 points 3 days ago

No, sapphires are any color corundum besides red. Red corundum is called ruby. The molecular formula of corundum is Al~2~O~3~

If it's not corundum, it's not a sapphire. Topaz isn't a sapphire. Emerald isn't a sapphire. There are yellow sapphires and green sapphires, but not every yellow or green gemstone is a sapphire.

[–] FishFace@piefed.social 13 points 4 days ago (2 children)

Rubies and sapphires are both the same mineral with different impurities but this is very wrong. Tourmaline, garnet, spinel, emerald, topaz, beryl, ...?

[–] Jesus_666@lemmy.world 14 points 3 days ago (1 children)

I was going to point out that some of the stones you mentioned are semiprecious stones but it turns out that "gemstone" actually includes precious and semiprecious stones. Also, the distinction between the two is arbitrary and mostly based on how expensive they were in the Copper Age. TIL.

[–] CommanderCloon@lemmy.ml 1 points 2 days ago

It's so arbitrary that Amethyst used to be one of the most expensive precious stones, before huge mines were discovered and it lost its status

The split of semiprecious vs precious is essentially 18th century marketing BS, it's not relevant nowadays, even to jewelers.

Some of the most expensive stones aren't even part of the "precious" stones because they were discovered recently, and since the term is obsolete even to jewelers there's no one to push the term on those new gems, like Alexandrite (which is more expensive than diamond)

[–] OwOarchist@pawb.social 7 points 4 days ago

Beryl and emerald are also (basically) the same thing. Just different impurities giving a different color.

[–] Dremor@lemmy.world 2 points 3 days ago

Not exactly.

Saphirs are Corundum of any colors exept red, because red Corundum are rubies.

So yeah, almost all Zelda games rubies are in fact saphirs.

Emeralds are Beryls, like aquamarines.

[–] mycodesucks@lemmy.world 32 points 3 days ago (3 children)

Every time I see people in the west mock Japan for being bamboozled by KFC into accepting chicken as part of Christmas tradition, I think of this.

Turns out people in general are just easily manipulated creatures of habit and custom.

[–] teft@piefed.social 4 points 3 days ago (3 children)

Why would americans mock japanese for eating chicken on a holiday? We do the same with turkey on thanksgiving which isn’t much different than kfc other than who made it. Everyone on this planet is brainwashed a bit by their ancestors.

[–] SaveTheTuaHawk@lemmy.ca 1 points 1 day ago* (last edited 1 day ago)

Eating eggs and bacon for breakfast, breakfast cereals, milk, orange juice, were all the result of ad campaigns.

People used to eat dinner leftovers for breakfast.

[–] chuckleslord@lemmy.world 9 points 3 days ago* (last edited 3 days ago)

It's not chicken, it's KFC specifically. That's usually the source of derision. Not to say I agree with it (let people have their little things, even if it's corpo hell paste that they got it from)

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[–] village604@adultswim.fan 3 points 3 days ago

The problem is that jewelry grade diamonds are still rare, even without DeBeers fucking with the supply.

Diamonds are super common, but they're mostly small and garbage quality (relatively).

[–] shalafi@lemmy.world 2 points 3 days ago

And where can this sentiment be found?

[–] Exusia@lemmy.world 28 points 3 days ago (2 children)

Something that often gets lost here is high quality gemstones are still rare by comparison. Not saying it excuses their stupid prices, but that we use diamonds to coat sawblades because it is so abundant, yet so much is shit quality.

Large enough to set in jewelry, with few enough imperfections to convince a buyer, and a skilled jeweler with years of practice cutting it, is still rare and worth something. Sure debeers did a "fuck you i control the supply" and we're still falling for part of that scam, but it doesn't mean gemstones are suddenly commonplace and worth $10.

[–] MonkderVierte@lemmy.zip 7 points 3 days ago (3 children)

Maybe we should embrace imperfection as a character of the gem.

Wait, no, then they use it as distinction to cheap artifical diamonds.

[–] SippyCup@lemmy.world 12 points 3 days ago

We should stop using them as stupid vanity items and working people to death to drag them out of the ground.

[–] THB@lemmy.world 8 points 3 days ago

They started marketing things like "chocolate diamonds" that are imperfect

[–] SaveTheTuaHawk@lemmy.ca 1 points 2 days ago

Maybe we should stop assigning fake value to a useless chip of rock.

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[–] Etterra@discuss.online 10 points 3 days ago (2 children)

Yeah diamonds are actually really garbage with a really good PR campaign, artificial scarcity, and PR. I remember some years back when they were really pushing "chocolate diamonds." They were just brown diamonds that they couldn't get rid of otherwise. I don't know if it worked, but I don't think so.

[–] quick_snail@feddit.nl 10 points 3 days ago (1 children)

Garbage? They're pretty fucking hard. That's a useful property

[–] filcuk@lemmy.zip 10 points 2 days ago (1 children)

Great for drill bits and my knife sharpener

[–] quick_snail@feddit.nl 2 points 2 days ago (1 children)

Please tell me you use ceramic for the knife sharpner 90% of the time?!?

[–] filcuk@lemmy.zip 1 points 2 days ago (1 children)

Haha I have 6K and 1K stone, then diamond 400 for rough edges and 150 for leveling the stone. Appreciate the concern though, the state of some people's knifes makes me uneasy

[–] KingGimpicus@sh.itjust.works 1 points 2 days ago* (last edited 2 days ago) (1 children)

As long as you understand that carbon steel blades/bits can and will dissolve the diamond right out of your sharpener.

The steel is hungry and cares not from where the carbon flows.

[–] filcuk@lemmy.zip 1 points 2 days ago

I don't think that's true. That only happens at extreme speeds/heat, not when sharpening knives by hand.

[–] LodeMike@lemmy.today 3 points 3 days ago

Big diamonds are actually rare. Still inflated.

[–] psx_crab@lemmy.zip 22 points 4 days ago

Diamond is expensive because it absorbed the miner and slave's blood. Gotta let it marinated for 24 hours.

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