Assorted stuff about glass bottles, because it is very rare that anyone might care about this stuff I carry around in my head:
At a previous job I worked on the control systems for machines that make glass bottles. The customer was the largest manufacturer of glass bottles in the US, and nos. 2,3,&4 purchased the machines from them.
Glass bottle making is an extremely low margin business. 2% was the figure thrown out when we started trying to improve the machines. The raw material is sand, and recycled glass, which are both virtually free. There was mention upthread of recycled glass being used for non-food use, which is not correct. Melting glass requires extreme temperature, and any impurities are going to get cooked out. Also consider that the alternative to recycled glass is sand which is full of dirt and germs, only so much of which will be washed out when it is cleaned. So food jars get recycled glass just like everything else. Any rejected bottles go back into the melt…not so much to save money on the cost of raw material, as to avoid the cost of hauling them away.
One example of how optimized the business is: The cardboard boxes and six pack carriers go to the glass bottle factory, and are used to pack the empty bottles in for shipment to the bottler…they have to be packed in something to avoid breakage, and no point in creating two sets of packaging.
Anyway, since there is virtually no cost associated with the raw material, the cost of the bottles is plant and machinery capitalization, labor, and fuel. Our goal was to improve the output of the machines by 2-4% which was expected to make them 2-3X more profitable to operate. (recall existing profit margin was 2%)
Brown glass is popular for beer bottles mostly because it is easiest to make. Nobody cares the particular shade of brown. Green glass is a little harder, but it carries some cachet, so it persists. Clear glass is the hardest…scrap glass has to be sorted, and only snow white sand can be used. Baby-food jars have the highest reject rate because moms don’t want to see a single dark fleck in that jar.
The manufacturing of bottles is so efficient, that inspecting and washing returns costs more than making new bottles. Also twist off caps are now a consumer expectation, and the threads do not reliably last more than one capping. Non-refillable bottles can be made thinner and cheaper, and lighter/smaller, so cheaper to ship.
Sorry, I never knew exact numbers on the cost, and it has been almost 20yrs. since I left that job, so anything I knew would be dated anyway.