Butte, Montana ribbed bottle *base only*

[Still]

Hi all,
So on my recent creek walk in North Carolina, I recently discovered this rather larger, aqua, ribbed base to a bottle (or jar?) from Butte, Montana. Appears to blown or very early machine made? Any ideas and pointers would be appreciated.
Cheers
- Still

 

[shotdwn]

That is the bottom of a coke bottle. Probably a 12 oz.

 

[CanadianBottles]

Quite a recent one too, I'm afraid. No earlier than the 1960s or so, and could be a fair bit later. Not sure of the exact progression on the later base designs but it's definitely one of the newer styles.