So, I was recently given a coal forge from a guy who got it years ago but never used it. And he also gave me a small barrel of some black substance. He couldn't tell me what it was only that the man who gave it to him said it was something good for blacksmithing and hard to find.

Flux, coal, abrasive, powdered black boogers, tar, bitumen, ---I have something green that is supposed to be good to eat---what is it?

Does it burn?  Is it solid or granular or liquid (and if a liquid how viscous?)

Any idea of what type of blacksmithing it might be good for?

Is it fine and slippery between your fingers? 

It is called Plumbago. An old name for not very fine graphite. 

If my guess is correct. 

i surely hope it is not black powder

So, I was recently given a coal forge from a guy who got it years ago but never used it. And he also gave me a small barrel of some black substance. He couldn't tell me what it was only that the man who gave it to him said it was something good for blacksmithing and hard to find. We think it might just be coal. It kind of burnt like it when we hit it with a plumbers torch. But coal isn't hard to find. I have no idea what it is but here's a pic 

Useful for punch and drift lubrication if plumbago.  Bit messy to use though, mix it with oil or grease and dip the punch or chisel in it every couple of hits.

Yep ... we used to finish work like lamps or small sculptures with it.

Paint with matt black paint and when still tacky rubb plumbago with a rug dipped in the powder. it gives the piece a metallic finish and it will never rust. 

If you like it to seem to be rusting a bit. paint with oil based paint that is the colour of rust. When still tacky apply plumbago with a rag, but sparingly this time letting streaks of red show here and there. 

Also good for rubbing your cast iron woodfire heater or kitchen, and if you are a railway enthusiast, it was the product of choice to rub all over steam locomotives. 

Depending of procedure it may not be any good as a lubricant. Originally plumbago was mined and it was pure, Today it is expensive relatively speaking so for rust prevention and to mix with paint it is produced by recycling electric motor brushes. The glue that keeps the graphite together in a brush is abrasive so the resulting powder is not particularly good as a lubricant, so don't add it to your chainsaw oil ... and don't ask me how I know

Well, that pic was not there before  

Seems way too rough to be plumbago, but you never know. Is it soft to crush? Can you rub it on paper and write like with a pencil? 

So is that charcoal made from the plumbago plant?

I don't know what that stuff in the photo is without more info from the OP.

Plumbago is an old name for graphite. it was called that way because it looks like lead. Ergo the name lead pencil. No real lead in it. Graphite is pure carbon and a product of millenia underground

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