Has anyone ever seen one of these?
It is a soda bottle (I assume) from the ROUNDUP BOTTLING WORKS, Roundup Montana.
It says BOTTLE PAT DEC 29 1925 above the Indian head.
What you have here is a big chief bottle. Very collectible and sought after by collectors. 1925 is probably a close guess on the year that bottle was made. Some rare big chief bottles can fetch 100's of dollars but I wouldn't believe yours is one unless it is a tough town to find. Easily your bottle in good shape is a $10+ bottle. Do a search on Ebay for big chief bottles you will see some very nice ones. Hope this helps some.
Brian
Brian, I spent about two hours looking for any info on Roundup Bottle works, I couldn't find a speck on the net, I bet his city is possibly one of the more rare breeds, of course I'm wrong pretty often[].
BOB