|Scratch brushes: brass, at top, with "bristles" extended and fiberglass, at bottom, with "bristles" retracted|
They are designed to remove buildup of oxidation (and crud) from jewelry. Their proper name is a scratch brush. I ended up ordering one each of the fiberglass and brass variants from Amazon (I am actually an Amazon Prime member to get their data storage, but loathe giving money to
In addition to fiberglass and brass, steel "bristles" are another option. Replacement bristles can be ordered as needed. These tools are about the size and shape of pens. By turning the top of the handle, one can extend or retract the bristles. The shorter the bristles, the more roughly they "score" the surface. After about two strokes across a styrene flat car deck, I realized these are amazing tools for weathering. I cannot recommend them highly enough. I will provide a separate post that highlights some of their capabilities. Until then, buy some of your own and use them liberally.