The repetitive imagery and standardized format evokes the look of mechanical reproduction, but the black outlines were probably stamped by hand from a single carved woodblock onto green areas printed in a grid pattern.
This engenders subtle differences in the work’s pattern; each of the bottles differs in both the evenness of the green underpainting and in the clarity of its stamped profile.
Only a few years ago bottles in these two categories rarely brought more than a few dollars but as interest in these categories increased so did the price. Whenever demand increases or outstrips the supply of a collectible, the price goes up.
Digger Odell's Antique Bottle & Glass Collector Magazine Price Guide Series has volumes different categories listing thousands of antique bottles that have sold at auction.
Some collectors even trade single vintage playing cards from beautifully illustrated decks.
Antiques dating from the late 1800s into the early 1900s, however, have priced themselves out of the market for the average collector.
The bottles are also often slightly askew, disturbing the overall regularity of the grid and making them appear simultaneously handmade and individualized, streamlined and mass-produced.
In his deadpan and ironic way, Warhol at once criticized and glorified the consumerist idols and surface values of America’s media-saturated postwar culture.
All bottles made before the turn of the century are partly or completely hand blown and formed.
Bottles made after about 1914 were produced in much greater number by machine (ABM for Automatic Bottle Machine).
"Coca-Cola" embossed in script letters contained Coke and is more valuable, while the "Coca-Cola" embossed in block letters contained a flavored drink other than Coke so is less valuable.