i have seen varnished, or rocks covered with what i would call old school varnish here in pa. i do not know the original origin of them. all were small, kinda like square with the edges semi polished off. i never found them in the streams though as those are most always flat and nicely rounded edges. i know what we have here sure is not gold though. my county sits on a sheet of non blended lava flow that looks like the malpais. i know, i ran the tunneling and boring crews here for 40yrs. darn hard stuff.