Hi, im doing an extensive project on metal working during the medieval
and early industrial ages. mainly im trying to focus on how metal
working was done - such as what equipment they used, what metals were
common, and what materials they burned to heat up metals, etc.
Here is my list that im working on:
Bronze (Tin and Copper)
Early Steels (Iron worked on at higher tempratures)
Here is what I do know (from searching around, it may be inacurate):
Rough Melting Points:
200C - 330C - Lead, Tin.
400C - 1070C - Bronze, Brass, Copper, Silver, Gold.
1100C - 1600C - Iron, Steel, Nickel, Cobalt.
- Silver and Lead are mostly come from Galena.
- Gold is naturally occuring in nuggets.
- Copper comes from natural occuring copper.
- Coal comes from natural coal deposits or sea-coal
- Coke is a by product of coal.
- Iron comes from Hematite
- Charcoal is 'cooked' wood that can burn hotter then actual wood.
Here are my problems:
- Im not exactly sure how Tin, Cobalt, and Nickle appear in nature
(what ore you need to mine/smelt)
- I dont know the average temprature points of burning wood, charcoal,
coal, and coke using a kiln (and with or without a bellows and hearth)
- What did the act of smelting involve (other then turning up the heat)
- What other equipment was necessary to work with metal (other then a
kiln, bellows and anvil).
- Did any of these materials have traditional names (eg. sulfur =
brimstone, quicksilver = mercury)
- Were there any other materials used in smelting (such as limestone?)
Any info on the above will greatly help me.
Start by reading Agricola's "De Re Metallica" This stuff is enormously
well documented for your level of detail (I've probably got 6 foot of
bookshelf on just this topic). Something like the SCA Florilegium (web
search) will give you a more detailed booklist,
In general, the process of smelting involves taking steps to purify the
metal as it melts, as well as to prevent further contamination. Look
up the words "slag" and "dross" in a dictionary and you'll find out
what I mean. When you melt metal, the contaminants seperate and will
screw up the metal if not removed. Frequently steps to remove the
contaminants include physical (taking a ladle or spoon and skimming the
junk off the top of the molten metal) as well as chemical such as
adding excess oxygen to oxidize the contaminants or adding fluxes. The
most common flux is, as you mentioned, limestone. Today it also
includes borax-based materials and some other mineral materials. The
limestone reacts with the contaminants to form a physical compound
which can be skimmed off.
Hope this helps. Any home metalworking hobbiest who casts their own
metal uses fairly prehistoric methods compared to modern-day industrial
work. Their techniques aren't all that different. Check out
and look at some of his techniques.
Another topic I just thought of is that many medieval metalworkers had
a fairly primitive knowledge of the metals they worked with ie "Smelt
-->metal with these properties" not "smelt this ore, I get cobalt" like
we do today.
backyard metalcasting is a good site but it doesnt tell me the
specifics of what materials to use (ie flux) and where to use them. Im
also coming to the conclusion that blacksmithing had nothing to do with
smelting ore into ingots, that was more like metallurgy or possibly
also im wondering what types of furnaces were used to melt different
metals. i read something about reverberatory furnaces, and open-hearth