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Comment by nimbius | Hacker News Reader

I work sometimes in a metal shop where Tungsten alloys abound. This might be the stupidest hn post I've ever read.

You bought a piece of metal at vastly inflated prices for a very narrow range of performance over a specific set of conditions. Nothing more. Being the hardest isn't being the best. Tungsten is extraordinarily brittle. A hard drop on concrete could crack it.

I'd also argue without a MA (metal analysis or labsheet) you probably bought some tungsten. Lead, slag, tin and other undesirable byproducts also weigh a lot. Your cube, without proper inspection, may also be slightly radioactive as its likely sourced from scrap. This could be good or bad, but the cube most definitely isn't a meaningful purchase.

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Every material more dense than tungsten costs more than tungsten, and the same goes for anything that even close close. Only thing you need to do to determine if you were screwed or not is measure the density. Since it's a cube the only thing you need is a ruler and a scale.

As for the value to a consumer. That comes almost entirely from its density not its hardness, something you'd know if you read OP.

As for the "vastly inflated prices" if you have the ability to produce and sell 1 kilogram cubes with the side length of an inch and a half for significantly less than OP paid then you should consider selling that information and retiring.

What are the materials with similar, but lower, densities? WC, I guess, at 15.63 g/cc; what else?

Apparently wholesale tungsten costs US$30/kg, which is about one fourth the US$130 cost the guy paid. I'd think either wire EDM or wire ECM would be able to dice tungsten into featureless cubes for a lot less than US$100/kg. Its brittleness wouldn't be a problem.

Also, it could very easily be impure, or even not tungsten at all; lots of people have gotten tricked into buying tungsten-carbide jewelry they thought was tungsten, and tungsten carbide isn't even metal. The Amazon seller says it's actually 5% nickel and iron, though I'm not clear whether it's an alloy or a powder-metallurgy sinter using those metals as sintering aids. Alloys aren't necessarily less dense than their densest pure component, so impurities might not even lower the density. X-ray fluorescence would be a cheap way to detect heavy-metal impurities (though not, say, boron, carbon, or nitrogen).

The guy is excited about how it's durable and will last for a long time. I think he will be disappointed if it really is so brittle that he chips the corner off by dropping it on the floor. Probably the nickel and iron will prevent that.

> This might be the stupidest hn post I've ever read.

I don't know... Seems your own post has missed the mark pretty sharply as well.

To me, it was abundantly clear that the purpose of this tungsten cube is not for engineering or practical utility.

Yes, but it seems like the Pet Rock for this crowd. It's entertaining to give it a heft, but I doubt if it will see as much daily use as his amortization projection suggests.

I think a better desk objet is a Curta calculator.

> he purpose of this tungsten cube is not for engineering or practical utility.

I would think you can easily sell it for the same or better price. It's like gold. It's a capacitor of wealth

If it brings OP joy, it's a reasonable and meaningful purchase

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