Smelting Bronze
This time we made bronze straight from ores of copper and tin! After melting store-bought brass , we wanted to see if we could reach the temperatures needed to smelt bronze. Smelting is the process of extracting metals from ores as naturally found. Now, bronze is an alloy traditionally made of copper and tin, around the range of 90% copper and 10% tin, depending on what you're after. For example, bell bronze (for casting bells) is more like 80-20. My friend and neighbour Alex Moyle makes some of his sculptures with silicon bronze (which confusingly has no tin in it, but ~97% copper and 2% silicon), like his latest of Pam McConnell: At the Pam McConnell Aquatic Centre Copper can but does not usually appear in nature as a ready-to-go, orangey-brown metal; it is more commonly found as an ore. That is, a rock with a higher-than-normal amount of copper mineral within it. One common copper ore is malachite, which looks like this: photo by JJ Harrison The copper in malachit...