The melting point of gold is 1337K, which is 1064 degrees Celsius, both to four significant figures, at standard pressure, that is, at 1 atmosphere, or approximately one hundred kiloPascals. The melting points of substances change with pressure, this is because as pressure increases, the compressive forces on the molecules increase and the metal ions (in this case, gold ions) cannot move out from the metallic lattice as easily and hence the average amount of kinetic energy (that is, temperature) that the ions possess must be higher to compensate for this increased force. The converse argument also applies and hence a decrease in pressure will cause the melting point of gold to decrease. The figure stated, 1337K, is only correct when the pressure is one atmosphere, (or 100 kiloPascals, the definitions of a standard pressure are different depending on which international system is accepted, however 100 kiloPascals is 0.986 atmospheres, so there is very little difference between the two) and still then is only correct for pure gold. Pure gold is hardly ever used commercially, as it is too malleable. Gold is blended with copper to produce a mixture or alloy, which can be used in industry or jewellery. The proportions in which gold and copper are mixed are measured in carats.
It is a well known story that Archimedes of ancient Greece, upon finding a way to test the purity of a gold crown without damaging it, ran through the streets exclaiming "eureka!" stark naked. He discovered that the density of a sample of gold differs with its purity, and so by a simple downward displacement of water, the purity of the gold crown could be estimated with no damage to the crown. Whether this story is true, an analogous property holds for the melting point of gold. Pure gold will melt at a much higher temperature than most of its alloys, the point where a mixture has its lowest melting point is called the eutectic point. In the case of gold and silicon (both of which have melting points above 1300K in pure form) the melting point of the eutectic mixture is only around 600K. However the eutectic composition of gold and copper only has a melting point of around 1100K, which is approximately 800 degrees Celsius.
For more information on gold, go on en.wikipedia.org/wiki/Gold This was, I found, the most helpful source in researching the properties of gold. A phase diagram of gold and copper can be found here at mtdatasoftware.tech.officelive.com/phdiagrams/aucu.htm
It is a well known story that Archimedes of ancient Greece, upon finding a way to test the purity of a gold crown without damaging it, ran through the streets exclaiming "eureka!" stark naked. He discovered that the density of a sample of gold differs with its purity, and so by a simple downward displacement of water, the purity of the gold crown could be estimated with no damage to the crown. Whether this story is true, an analogous property holds for the melting point of gold. Pure gold will melt at a much higher temperature than most of its alloys, the point where a mixture has its lowest melting point is called the eutectic point. In the case of gold and silicon (both of which have melting points above 1300K in pure form) the melting point of the eutectic mixture is only around 600K. However the eutectic composition of gold and copper only has a melting point of around 1100K, which is approximately 800 degrees Celsius.
For more information on gold, go on en.wikipedia.org/wiki/Gold This was, I found, the most helpful source in researching the properties of gold. A phase diagram of gold and copper can be found here at mtdatasoftware.tech.officelive.com/phdiagrams/aucu.htm
