The smaller soft drink and beer bottles gave way to aluminum cans just about the time I forced myself to believe beer did not "taste like shit". My high school buddy, Charlie, went off to pursue a Masters in Metallurgical Engineering, I was then already married, attending Junior College nights, also Engineering oriented.
The early Coors beer cans, (ever seen one?) had two circular embossed "cutouts" on top, one big to guzzle out of, the other small, to ensure the product exited as fast as possible. These circular pop-outs actually popped inward, settling to the bottom. A lot of inebriated folks must have swallowed those circular slugs of metal while imbibing, since soon, a newer (the current type) of closure (opener?) was introduced. They have a retainer preventing loss of the pop-off. My father-in-law hated them, twisted them 'till they broke loose, and then dropped them into the unfinished contents. He nearly choked on one a few times!
"Cutting to the chase", Charlie was becoming proficient in metallurgy, and I was "street wise" thereof, so I implored him to reveal, how in the hell do they make those aluminum cans? The earliest, two-piece, had steel tops, crimped in place. Later, tops became aluminum also. Anyway, I could never discern any kind of tool marks inside or out as clues: he claimed they were drawn from thin sheet stock, I thought that impossible, given the apparent hardness and springiness of the material, suggesting they were spun, like the stainless steel mixing bowls and such still commonly seen.
But, never resolved, HOW THE HELL DO THEY MAKE ALUMINUM CANS? jocular