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As seen on Game of Thrones the TV series, some gold is melted in a regular campfire.

http://www.youtube.com/watch?v=J74JEloKC3M

Is this physically and chemically possible?

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    gold melting point according to wiki: 1337.33 K, 1064.18 °C, 1947.52 °F and a quick google puts campfires at 480-1000°C depending on fuel Commented Aug 20, 2011 at 23:04
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    @ratchet A crown would likely be made from a gold alloy, not pure gold. The melting point of the alloy would be different then, though I don't know if it would be low enough.
    – Mad Scientist
    Commented Aug 21, 2011 at 7:29
  • Define "regular campfire", you know how many different tree's there are to burn. Some wood buns much hotter than others. I call it a bust.
    – Moab
    Commented Aug 24, 2011 at 2:40
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    @ Moab: I suppose it's something that an answer should address, not the question. If I already knew the subject so deeply I wouldn't need to ask in the first place.
    – user288
    Commented Aug 24, 2011 at 13:46
  • Anecdotaly, I have build a campfire that got hot enough to soften a glass bottle. Mind you, it was fuel with Texas live oak and we had a brisk, steady breeze blowing right between the two big base logs. Poking about on the internet seem to imply a temperature near or above 1000°F, still not really hot enough. Commented Mar 26, 2012 at 20:37

1 Answer 1

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Gold melts at 1064 °C, however, in jewellery, gold is often alloyed with copper (wiki). Though copper melts at 1084 °C, the alloy has a lower melting point, as you can see from the phase diagram (note that the temperature is in Kelvin, which adds ~271):

Au - Cu phase diagram

If the crown is 18k gold (¾ gold, ¼ copper), which makes an alloy that is harder than gold or copper alone, and gives a nice reddish hue to the gold, then the campfire only needs to be able to produce ~900 °C, which is achievable with the right fuel according to @ratchet freak's research.

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    Indeed. And if there are additional base metals introduced, like say tin, then you can achieve some impressively low melting points if the proportions are just right. Gold-tin has a eutectic point at 300C! pruffle.mit.edu/3.00/Lecture_36_web/node1.html Commented Jan 4, 2013 at 0:16
  • So it is possible chemically?
    – Mark
    Commented Nov 7, 2013 at 1:18
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    @ChristianMark: Not sure what you mean - alloying tin and gold is done by dissolving blocks of tin in liquid gold, and stirring. No complex chemistry needed.
    – Jonas
    Commented Nov 8, 2013 at 12:33
  • While a properly built pyre will certainly burn hot enough, the problem is getting the temperature all the way to the smelting pot. Without some insulating walls, i.e. a kiln, the pot will be losing heat too fast to get at the temperature (note: pottery kiln also needs ~900°, can be wood fired with free draft, but needs to be insulated to maintain the heat).
    – Jan Hudec
    Commented Apr 18, 2019 at 20:46

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