I am pretty sure that everyone have a different stockpile for many different items that could go on the same stockpile, for example, having entrails in a stockpile to use them to cook livers & onions and another stockpile for intestines to make Sausages, I have different stockpiles for every kind of metal, because in a stockpile I have Tin, to fuse it with Copper (in another stockpile) and then I put them in a stockpile of Bronze, because it have lower quality that Cast Iron, this one is in yet another stockpile.
Now, the problem is that when I forget what stockpile contains what, I have to take one item from it to remember, and I think it could be very useful to name a stockpile.
Another good solution would be that the stockpile have the name of the only item that is in the stockpile, if there's only one kind of an item, and the common name if there are more than 1 kind of item, for example:
Stockpile have only Cast Iron: Stockpile of Cast Iron
Stockpile have Cast Iron and Brone: Stockpile of Hard Metal
Stockpile have Tin and Bronze: Stockpile of Common Metal
Stockpile have Tin and Cast Iron: Stockpile of any Metal