It seems fairly universal that man figured out how to smelt bronze, then iron, then steel, etc. but how did they figure out smelting in the first place? It seems like it'd have a fairly large learning curve, especially before the tools themselves could be forged.
Hi OP,
You will probably get a better answer posting to /r/anthropology.
It's important to keep clear that smelting and forging are two separate steps. Smelting is the extraction of the metal from the ore. Forging is pounding on the metal to shape it or alter its microscopic structure.
The equipment for smelting does not require metal tools. Crucibles are [made of ceramic materials] (http://books.google.com/books?id=Y8ul6VAOMFcC&dq=Natural%20Refractory%20Materials%20Employed%20in%20the%20Construction%20of%20Crucibles%2C%20Retort%2C%20Furnaces%20%26.%20Metallurgy&pg=PA208#v=onepage&q=Natural%20Refractory%20Materials%20Employed%20in%20the%20Construction%20of%20Crucibles%2C%20Retort%2C%20Furnaces%20&f=false).
The common hypothesis is that smelting was discovered in the process of firing pottery in kilns, considering that the technologies overlap. Early copper smelting appears to have used wood fires
For most metals other than iron, forging can be done cold.
You are right that there is a bit of a chicken-and-egg problem. You certainly would rather be pounding on your iron bloom with a modern hammer, but you might be able to get by with a stone mallet until you've made enough iron to make an iron hammer, and so on.
Similar cycles of improvement take place in any technology. Watt's first steam engines had much larger tolerances until the techniques improved with the availability of the powered machine shop. Whitworth's first screws were much less precise than the later. The first integrated circuits were layed out with exacto knife and those computers were used to layout the designs for the next computers.
