gold

[sillygoosegirl]

Whoever said gold is soft was a big fat liar.

It's not soft; it's brittle.

And it's broke.

There's $150 down the drain.

Comments

[squirrelloid.livejournal.com]

Gold is fairly durable once its set. What makes it brittle is the stuff they add to it. 24k gold is really soft, and 18k gold is somewhat soft, but not to lots of movement at once. And it really depends on how warm it is - it gets brittle as it gets cold. But at human body temperatures, it kind of soft (wearing it will deform the ring over time).

Suggestions: (1) You can melt gold with stove range temperatures. Now, if you can only figure out how to make it into wire again, you're set, as that will make it one piece. (2) While braiding, work with it warm (id check some literature, but ~100F is probably good) but not melted so that its more flexible.

[camlost.livejournal.com]

I was thinking that heating it up might help... We've only lost about 1in, so there's probalby enough to make rings still. It's a question of being able to ever make rings given the material we have. It's possible that heating it up once might make it lose some of it's stiffness (it would go back to a more random state), and make it easier to work with. I doubt we want to melt it... besides, the melting point is 1947.52 °F, according to the first google hit. Hardly stovetop temperatures. The question is can we heat it hot enough so that it will not break and Mary can still work with it. I expect there is some temperature. I expect it might help a bunch to heat it in the oven and then cool it, which may very well reduce the hardness.

[squirrelloid.livejournal.com]

Um, well, thats how a goldsmith would work with it is by heating it.

I didnt realize its melting temp was quite that high, i was pretty sure you could melt it on a stove top - maybe im thinking 24kt gold, and 18kt has enough stuff added that its not as much of a problem.

You can't reduce hardness, its a property of the material. Nor do i think scratching it is what you are concerned about. I dont think you'll effect the strength of the material, especially at relatively small fractions of the melting temp.

[camlost.livejournal.com]

The number I reported was for pure gold. "18kt yellow gold melts typically at 895-930C" according to one site, which is similar to that of pure gold.

I expect that 18K gold metal has various different metal phases. Heating and (super)cooling the metal can change which phase it is in, and it's commensurate properties. I could be wrong about the different phases, though.

[camlost.livejournal.com]

For an example of how the phase diagram might be interesting, check out:

http://pruffle.mit.edu/3.00/Lecture_36_web/node1.html

The Au-Sn phase diagram shows several different states. The solid colors are pure states, and the lines are combination of states. The Au-Ag diagram unfortunately doesn't go low enough to be of interest.

[squirrelloid.livejournal.com]

My guess from those by extrapolation is that heating on the order we're talking about isnt likely to change anything. I mean, most of the variation is due to differing percentages of the two metals in many of the cases, or on really high temperatures. I doubt any temperature Mary would be willing to work with it at would be a problem.