What is anvil dust anyway?
It's created during the forging of steel items. Small flakes, also referred to as forge scale, come off as the metal is moved, from hammering, bending, and twisting. It heaps around the anvil and that is what I have heard it called the most. I have also heard it is called blacksmiths dirt. I like calling it anvil dust.
Some History I think that before we get into some uses, let’s take a stroll through some history, shall we. Back in the days of yore, (I so enjoy being able to use that word!) the blacksmith was held in extremely high regard. There wasn’t anything happening in the town or village that the smith didn’t have his hands on. From tools, to utensils, to weapons and so much more. I can’t think of an occupation that didn’t have dealings with the blacksmith. He was able to wield the elements to bring about change. The air from the bellows, an earthen forge, fire to heat the metal, the water to quench with and the spirit of the metal and the smith themselves. Looking at it from the lens of a medieval times person and before, it must have been seen as a very magical undertaking. I don’t think it is awfully hard to see how the blacksmith was considered a very mystical person. (I think this still!) It is not hard to understand how magical the very ‘dust’ around the anvil would be.
The Dictionary of American Regional English at the University of Wisconsin–Madison has some interesting notes going back to 1820 on some uses of anvil dust. From a rust remover, ingredient in a tonic, insecticide and more. Check it out, it's kinda nifty,
What I use it for
I’m personally a huge fan of anvil dust. To me it’s like a cross between duct tape and WD40. If it ain’t supposed to move, duct tape. If it is, WD40. And a little dab will do ya’. I put that stuff (anvil dust) on everything. I will add a pinch to my devotional candles for focus, along my house thresholds for protection, I will use to recharge my land wards, add to spell work and rituals to strengthen it (you’ve heard of 'iron will' right?), since it is magnetic it is great for attractions. And the list for me goes on.