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Lord Torath
2017-05-31, 01:24 PM
Anyone know the density of Adamantine and Mithril?

I've got the specific gravity (density relative to water, or density in g/cm3 for the "real world" metals:

Copper: 8.9
Silver: 10.5
Electrum: 8.4-8.9
Gold: 19.3
Platinum: 21.4

Ten pounds of platinum, for example, is a bar an inch square and about 13 inches long.

But how big is a 10-pound bar of mithril?

Honest Tiefling
2017-05-31, 01:30 PM
Uh...Electrum is an alloy with gold content ranging from 40-90%, I think you should probably just take that off the list unless you mean a particular type.

For Mithril, why not use aluminium as a base? I wouldn't be terribly surprised if that was the inspiration for the metal to begin with.

Lord Torath
2017-05-31, 01:34 PM
Uh...Electrum is an alloy with gold content ranging from 40-90%, I think you should probably just take that off the list unless you mean a particular type.This website (http://www.csgnetwork.com/specificgravmettable.html) says between 8.4 and 8.9, so I went with that. Who uses electrum anyway, though?

Honest Tiefling
2017-05-31, 01:44 PM
This website (http://www.csgnetwork.com/specificgravmettable.html) says between 8.4 and 8.9, so I went with that. Who uses electrum anyway, though?

In the ancient world, it was used for both jewelry and coinage. Today, it is more commonly known as green-gold and used to contrast with other colors (white, yellow, and red) of gold. I am guessing this site probably means the modern green-gold, which needs a particular balance of the metals or its well, not green.

Titanium is also a good contender for a comparsion for mithril at around 4.5 grams/cubic centimeters, making it far lighter then copper.

Knaight
2017-05-31, 03:07 PM
I'd use aluminum and tungsten for most of the material properties of mithril and adamantine, respectively. There's a few properties which need changing, which involves either just cranking them up (Moh's Hardness can hang out at 11 and 12 for them), or taking properties from steel alloys.

Mastikator
2017-05-31, 04:00 PM
Mithril is harder than tempered steel and when Frodo puts in on it looks more like a normal tshirt than a chainmail, so it should be very light, aluminum is probably a high (but reasonable) estimation.

As for adamantium

Very rough figures here:

Wolverine's weight: (without adamantium skeleton) 200 lbs., (with adamantium skeleton) 300 lbs. link

So adamantium skeleton weighs about 100lbs (45.36 kg)

An average skeleton's volume is about 6"3 (9.832 m3) link

45.36 kg / 9.832 m3 = 4.6135 kg/m3 Source (https://www.reddit.com/r/AskScienceFiction/comments/1ewbg7/calculating_the_density_of_adamantium_anybody/) (bottom)

So in spite of adamantium being described as "oh so dense" it's actually half that of iron.

hamishspence
2017-05-31, 04:03 PM
Mithril is harder than tempered steel and when Frodo puts in on it looks more like a normal tshirt than a chainmail, so it should be very light, aluminum is probably a high (but reasonable) estimation.

As for adamantium
Source (https://www.reddit.com/r/AskScienceFiction/comments/1ewbg7/calculating_the_density_of_adamantium_anybody/) (bottom)

So in spite of adamantium being described as "oh so dense" it's actually half that of iron.

I was under the impression that the Adamantium didn't replace the bones, but was a thin layer covering the bones.

Beneath
2017-05-31, 04:27 PM
Fictional materials aren't going to have consistent properties across different bodies of work.

D&D3 treats mithral as being half as dense as iron (considering you can make pretty much anything out of mithral that you could out of iron and it'd weigh half as much) and adamantine as having no significant change in density between it and iron, or any density change can be made up for by varying thickness. Mithril in LotR is likely significantly lighter (also note the spelling difference; mithral is legally distinct from mithril in much the same way as D&D halflings are legally distinct from hobbits)

Lord Torath
2017-05-31, 04:27 PM
I'm going to call out that figure of 9.832 m3 as extremely questionable for the volume of a human skeleton. One cubic meter is roughly the size of a washing machine. There's got to be a slipped decimal in there somewhere. What did they mean by 6"3? Six cubic inches? A cube six inches on a side (216 in3)? Something's wrong there.


Fictional materials aren't going to have consistent properties across different bodies of work.

D&D3 treats mithral as being half as dense as iron (considering you can make pretty much anything out of mithral that you could out of iron and it'd weigh half as much) and adamantine as having no significant change in density between it and iron, or any density change can be made up for by varying thickness. Mithril in LotR is likely significantly lighter (also note the spelling difference; mithral is legally distinct from mithril in much the same way as D&D halflings are legally distinct from hobbits)So Mithril (AD&D D1-2 spelling) has roughly the density of Titanium (4.5 g/cm3), while Admantium would likely be closer to 8 or so.