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> Of all of my desk toys/models/prints it's generated the most talk amongst friends and coworkers.

I'm not joking when I say one of the things I miss most about office life is decorating my desk with objects and having people react to them. Even before Delta, when things were opening back up, my office was doing "hot desks" which meant you didn't really get to personalize your space. It's understandable, but a bummer.

Do you have some kind of work chat room(s)? Just share pics or videos there. No it's not really as satisfying, but it's still fun.

For context, iridium is probably the densest material you’d want for a paperweight [1] but it’s rarer and more expensive than tungsten or platinum.

[1]: https://www.quora.com/What-is-the-heaviest-metal-I-can-legal...

https://luciteria.com/metal-cubes/iridium-metal-cube-9995

$9,000 for a 1cm cube. That's "winning the lotto impulse purchase" level for me.

It's not like that money disappears. Just think of it like buying gold bullion.

Unlike say, a $9000 motorcycle impulse purchase, a block of raw metal should hold it's inflation adjusted value relatively well for decades and you can sell it whenever to recoup the money.

Gold bullion has a healthy market to sell back into though.I don't know the numbers, but i wouldn't be surprised if I could easily sell gold for 80% of "market" value, whereas probably closer to 20% for something like Iridium that has a very small adressable market unless I were to expend considerable effort finding someone willing to pay what it's worth.

Platinum might be a better fit in this "really heavy" category. 21.447 grams/cc versus gold at 19.3 grams/cc.

Iridium is commonly used in jewelry; it's one of the platinum group metals.

It doesn't have the mass awareness of gold, but it's not some weird niche material either.

You could probably sell it to just about any gold dealer, as a lot of them sell iridium bars anyway. The tools they have to verify the purity of gold also work for other metals. If not, then they would certainly have connections to find someone who will buy it.

Also, you generally buy/sell on a 5-10% spread from the "spot" market price of the metal, depending on the quanitity you're dealing with. Dealers generally offer a closer price to spot when dealing with larger dollar value amounts of metal.

New form of investment?

Metals also survive pretty much anything, including catastrophic fires.

Gold can easily melt in a house fire. A diamond ring can turn into a puddle of gold and no diamond because it burned off

Melted gold is just as valuable as gold jewelry, since they melt it down anyway when you sell it. It might be worth marginally less than an intact piece of gold bullion that can be resold without processing.

Diamonds don't have resale value anyway. They're literally a scam.

One thing I've wondered, exactly how easy would it be to find a gold puddle after a fire anyway? I mean it's not going to vaporize or walk off on its own, but is it just going to be a little solidified glob there to pick up or what?

Yes but it will probably be blackened with soot which will make it hard to find.

Yes, it might flow around in the fire but it would be in the same area. A metal detector would be the fastest way to find it. Likely less time to find it solidified than looking for jewelry on a beach. Certainly less time than mining the gold.

I've found aluminum globs under fires that had cans or trashed roofing thrown in. Pretty clean, since nearly everything floats on it, and easy to spot in ashes.

Aluminum melts around 1200F. That’s a really hot fire! Was it a windy day?

(Lead, on the other hand, melts at half that.)

Once the core of the fire is mostly charcoal temperatures can climb up to 1100C. It doesn't have to be windy or even a large fire. Just need to be burning charcoal and not evaporating water or burning off volatiles.

The fires I have found aluminum globs in were long burning beach campfires and a bonfire to burn brush(big fire). The beach campfires were moderately sized but they certainly weren't bonfires built with 6-8 foot logs.

Diamonds do have significant markup depending on where it is purchased but they do still have some value. As long as the buyer can verify the certificate and the diamond is of significant quality, size, clarity, etc. it still retains value. A gemstone buyer may offer less than a private buyer (just like with cars) because they are in the business of selling the diamond later for a profit. Obviously, there is artificial inflation from the manufacturers but everyone else still has to play in the inflated market.

As for gold jewelry, this can swing both ways. An intricate piece with some sort of history attached may fetch a higher price from a buyer that is interested in that versus a scrap buyer that will just melt it down.

Similar analogies can be found with cars. A factory stock 1996 VW Golf will only be worth slightly higher than scrap value. Meanwhile, a 1996 VW Golf Harlequin will be worth $8-9k, its the same car but with a different factory paintjob. Effectively no difference in manufacturing costs since it was just made from different stock-painted panels but worth way more to a buyer simply due to the history and rarity. The cars both still have the same scrap value, a junkyard would buy both of them for the same price.

That's my point. Gold changes shape in a fire, but it's not lost.

I'll get myself a 10cm cube as a paper weight when I start and sell my multibillion asteroid mining startup.

I mean with any luck we'll find a pure iridium asteroid and bring the thing back to earth. Iridium paperweights for everyone!

To save people some time clicking through...

A 10mm cube of Iridium weighs ~21.9g. And from this source, costs $9000.

From the same source, a single gram is only $275. This means that due to the difficulty in working with this very dense metal, the cost of turning the Iridium into a cube is nearly $3000 (on top of the ~$6000 for the metal itself)!

Osmium would be heavier still (22.59 grams/cc), and a relative bargain at $1275 for the 10mm cube at the same source. Not polished/shiny though.

And, as divbzero's Quora link points out, it's going to kill you by oxidizing into a toxin when exposed to open air.

That seems to be a concern with osmium powder, ground osmium, etc. I don't think that a cube has any handling requirements more exotic than lead solder.

Less than that even. It's a noble metal and doesn't like to react under normal conditions, though hitting it with a blowtorch might ruin your day.

Osmium is the densest pure metal, but iridium has an almost identical density, i.e. 22.56 for Ir, vs. 22.59 for Os.

The difference is far too small to give you a different feeling when holding a piece of either osmium or iridium.

While osmium and iridium are the densest pure metals, there is a range of composition in the osmium-iridium alloys which has a slightly greater density than both pure osmium and pure iridium.

That happens because the atomic concentration of Os is a little higher than that of Ir while the atomic mass of Ir is a little higher than that of Os.

While increasing the proportion of Ir in an Os-Ir alloy from 0% to 100%, there is a range where the atomic concentration decreases slower than the average atomic mass increases, so the density of the alloy becomes greater than the density of pure osmium.

At higher Ir percentages, the increase in atomic volume overcomes the increase in atomic mass, so the density becomes a little lower than for pure Os.

Unlike pure osmium, an Os-Ir alloy would not be dangerous to handle. Pure osmium is slowly oxidized in air releasing the volatile and extremely dangerous osmium tetraoxide.

In nature, the normal occurrence of both Os and Ir is as nuggets made of Os-Ir alloy, usually also containing ruthenium and very small quantities of rhodium.

Theodore Gray has a story about visiting a company with an electron beam furnace with Oliver Sacks to turn a pile of loose iridium beads into a bar: https://theodoregray.com/PeriodicTable/Stories/077.x3/index....

Some of the cost isn't just from using the equipment, but because you'll have some evaporation from melting in vacuum. He says at the start of the article that Sacks started with a kilogram of beads:

>After melting from both sides and a lengthy cool down period (plus a couple of "ouch, where are my gloves" moments) Sacks' iridium was consolidated into a block a little over 2" square and less than 1/2" thick, weighing 1.7 pounds. It's startlingly heavy, distinctly more so than a similar sized tungsten block (which would be about 15% lighter and about 10,000% cheaper).

If true, the melt lost 22.7% of the mass, which is pretty painful. Google is saying iridium is about $167,000 per kilo right now! I assume they've got a cold trap on the vacuum line, and recovered some of the difference in weight as fine iridium dust, but the rest is going to end up coating the inside of the vacuum chamber.

If they routinely melt platinum-group metals, I wonder how often they scrap the entire chamber to melt it down and recover the evaporate.

Normally all furnaces or vacuum chambers where precious metals may evaporate have their walls covered with some metallic foil, e.g. aluminum foil (while the worked metal is heated at very high temperatures by the electron beam, the walls remain much colder), on which the precious metals lost during heating will condense.

After a production batch, the metallic foil is replaced and the used foil is chemically processed and almost 100% of the precious metals are recovered.

Ah, that makes a lot more sense.

That story reinforces everything that I've learned about Oliver Sacks. What a cool dude.

Blocks of magnesium are not fire hazards are they?

Magnesium only ignites easily when in thin strips?

yeah, needs a strong heat source if it's a block. E.g. it's tricky to ignite a NeXTCube even with a blowtorch: https://simson.net/ref/1993/cubefire.html

"easily" is a relative term, it'll absolutely go up in a glorious blaze among any other actual fire but it won't set off at the slightest spark like fire starting powder or strips.

It's also a relatively pure sample, very soft, not an alloy like you'd see with magnesium casings. The block is actually a little deformed just from dropping it on the floor once.