Yeah, I can’t ignore all the cool words one uses while metalworking. Not only because the Settlement has a blacksmith, but because my “real job” involves solder and flux and dross, and aren’t those COOL words?
Okay, here we go.
Ore is the unrefined version of any metal–it’s what you dig straight out of the ground, or pull off the bottom of a lake, in the case of bog iron. It usually doesn’t look like much.
If it’s iron ore, you might use a bloomery to refine it. That’s a primitive oven used to heat the ore with charcoal. The ore and charcoal react with oxygen, and two things drop out the bottom of the bloomery: slag, which is all the impurities you don’t want (except that the first run’s slag often has enough iron still in it to be worth putting through the bloomery again), and bloom, or sponge iron. This is the refined iron, which drip-drops into a big wad. It’s full of bubbles, which is how it gets it name.
Next you need to forge that iron. That means you heat the bloom and beat it with your hammer, again and again. This beating will work out more slag, and leave you with bar iron, the unformed version of wrought iron. Note that forging wrought iron is a primitive, fairly simple process. Making cast iron, on the other hand, requires temperatures and chemicals the world didn’t get its hands on in large quantities until the 19th century. It’s also worth noting that in the opening of season 4 of Game of Thrones, they cast two bloody swords, which is not how bloody blades are bloody made (they’re forged), but whatever. I guess it looked cool.
If you are melting metal, the melting process invariably brings out some impurities. These are called dross. One metal commonly melted is solder, which is a generic term for any low-melting point alloy used to attach two other pieces of metal to each other. To ensure the solder will flow properly, you wet your metal pieces with flux, which is any of a number of substances designed to do that job.
Two pieces of metal can also be joined by brazing, which is similar to soldering but happens at a much higher temperature and gives neater results.
A third technique for joining two metals is welding. In this process the two pieces of metal are actually melted together, unlike soldering and brazing, in which the basic pieces are unchanged.
I’m by no means an expert on all this. If you want more information on any of it, Wikipedia and YouTube are great places to start. If I’ve gotten anything wrong, by all means let me know, and I’ll fix it.
Hope you enjoyed!