Soda bottles are valued based on scarcity, shape, color and bottling location but not always on age. “Petretti's Coca-Cola Collectibles Price Guide (11th Edition)” is an excellent reference to use as a starting point.
The rarest soda bottles are the early Hutchinson Coke bottles, used in bottling from the mid-1890s to the early 1900s. Soda pop gets its name from these bottles. The bottle stopper features a sealed neck that opens by pressing down on a metal loop attached to the stopper, breaking the seal and making a popping sound.
The period from 1900, when the Hutchinson bottle was phased out, to 1919, when the familiar contour bottle becomes standard, is of greatest interest to collectors. A variety of straight-sided cylinders and segmented, round, textured and embossed bottles come from this era. They feature diverse sizes, markings and colors ranging from clear to green, aqua, blue and amber. Values range from $25 to $400, depending on condition and rarity.
The flared hobble-skirt Coke bottle, with its four-digit number identifying the mold and year of manufacture, dates from 1916 and is still used today. Earliest bottles are of several colors, but after 1923, all Coke bottles are green tinted except for the ones manufactured during World War II, which are blue because of copper shortages. Collectors are often disappointed to find that even very old contour bottles are not particularly valuable because so many are still available.