mod vintage ice textured glass drinking glasses, square base tumblers St Regis?

Set of six unmarked glass tumblers, ice textured crystal clear glass, square heavy base with round bowl. Libbey St. Regis?

These are about 3 3/4" tall (8 ounce size, I'd say). All six of these glasses are in very good condition, no chips, very little scratching from use.