These aren't insulators of course, but the crown seal beer certainly is related, as it was manufactured by Western Glass Mfg. Co., and has the 'belt buckle' marking on the base. It is a Neef's bottle, and so embossed. Neef's was a local brewery here in Denver, until statewide prohibition put then out of business in 1914, this bottle being manufactured in the 1901-1908 era. $12 plus $5. The other bottle, a hutch soda, is from Colorado's earliest glass bottle-making venture, Colorado Glass Works of Golden. William Modes had some attachment to this firm, according to research done by Denver glass specialist Mike Miller. They were only in existance during 1887 and part of '88, and any so-marked bottle is quite scarce. Embossed Colo. G. W., and base embossed, 'A A MARSELIS DENVER, $20 plus $5. The toll has two base chips, one being about an inch long, but displays nicely, is $10 plus $5.