An Alloy is a blend of a metal and other metals or minerals.
Standard modern alloys (using modern names) for jewelry include:
- Brass - High
- Copper 65%, Zinc 35%
- Brass - Low
- Copper 85%, Zinc 15%
- Brass - Tough
- Copper 55%, Zinc 44%, Tin 0.5%, Aluminum 0.5%
- Brass - Red
- Copper 85%, Tin 6%, Zinc 5%, Lead 4%
- Brass - Yellow
- Copper 67%, Zinc 31%, Lead 2%
- Brass - Bearing
- Copper 82%, Tin 14%, Zinc 4%. Used in heavy machinery.
- Automobile Bearing
- Copper 80%, Tin 10%, Lead 10%. Used by many automobile manufacturers.
- Bronze - Bell
- Copper 75%, Tin 25%
- Bronze - Phosphor
- Copper 80%, Tin 15%, Zinc 5%. Used for boat building. Uses a flux of phosphorus when melting.
- Bronze - Monument
- Copper 87%, Tin 7%, Lead 3%, Zinc 3%
- Sterling Silver
- 92.5% Silver, 7.5% other metals, typically copper. Harder than pure silver, but the copper component oxidizes.
- Silver Solder - Hard
- Silver Solder - Medium
- Silver Solder - Easy
Bronze and Brass definitions from Payne, Art Metalwork with Inexpensive Equipment, pp. 24-5.
Regardless of the names above, the definition of bronze is an alloy of copper whose main secondary component is tin. Brass is an alloy of copper whose main secondary component is zinc.
Theophilus has this to say about making "coarse" brass:
Chapter 66. Making Coarse Brass
And when the crucibles are red-hot take some calamine, about which I spoke above [III-63], that has been [calcined and] ground up very fine with charcoal, and put it into each of the crucibles until they are about one-sixth full, then fill them up completely with the above-mentioned [crude] copper [III-63], and cover them with charcoal. From time to time poke the holes below with a slender hooked stick, so that htey may not become blocked and also so that the ashes may come out and more draft may enter. Now, when the copper is completely melted, take a slender, long, bent iron rod with a wooden handle and stir carefully so that the calamine is alloyed with the copper. Then with long tongs raise each crucible slightly and move them a little from their position so that they may not stick to the hearth. Put calamine in them all again as before and fill them with copper and cover them with charcoal. When it is once more completely melted, stire again very carefully and remove one crucible with the tongs and pour out everything into [little] furrows cut in the ground. Then put the crucible back in its place. Immediately take calamine as before and put it in, and on top as much of the copper that you have [just] cast as it can hold. When this is melted as before, stir it and add calamine again and fill it again with the copper you have [just] cast as it can hold. When this is melted as before, stire it and add calamine again and fill it again with the copper you have [just] cast and allow it to melt. Do the same with each crucible. When it is all thoroughly melted and has been stirred for a very long time pour it out as before and keep it until you need it. This alloy is called coarse brass and out of it are cast cauldrons, kettles and basinss. It cannot be gilded, since the copper had not been completely purged of lead before the alloying. If you are going to make brass which can be gilded, begin in this way.
Hawthorne and Smith, On Divers Arts, pp. 143-144.