set of four brown ceramic ashtrays

From a quick visit to Goodwill today, because I like collecting ashtrays and they were cheap-ish, this set of four stacking individual ashtrays. Made of chocolate brown glazed ceramic, they're about 4" square with one higher side for the single cigarette rest on each, being square they can be stacked as in pic 1 or turned any which way. They are completely unmarked and I don't have any idea how old they are, I'd guess relatively contemporary items even though ashtrays aren't nearly as popular a 'decor item' as they used to be....if not actually intended to be ashtrays I suppose they could be spoon rests, or they could certainly be used as coasters...they'll be ashtrays in my house, though... ;-) <lol>