>Is the use archaic?

hmm... I suppose, a bit

I would say no. Fine gold, for example, is understood as (re)fined metal. Also, fine(s) as a description of particulate material is quite common in the building trade about aggregates - if you specified "crusher run including fines" it would be all-in ballast from sand upwards, contrasting to say a grade of crushed rock like "½-inch to 3-inch".