Theodore Gray @ PopSci writes –
All the components of glass can be found in two places: the beach and the laundry room. Itรขโฌโขs possible to melt pure white-silica beach sand into glass, but only at temperatures of 3,000 to 3,500รยฐF. Washing soda, lime or borax (a traditional laundry aid) added to the sand disrupts the quartz-crystal structure of silica and reduces the required temperature to a more practical, though still dangerous, 2,000รยฐF, which I achieved with a backyard grill and a vacuum cleaner. Glass is thought to have been discovered around 7,000 years ago by Phoenician merchants when cooking fires were built over sand that, by chance, had some of these substances mixed in.
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