Last Updated: Jul 20, 2017 Views: 82
The Chemistry of Glass provides great charts and information on temperature and types of chemicals used. Thousands of different compositions can be made into glass and there is no one composition that characterizes all glass, so there's a lot of different answers based on what is being used to make glass. Our Hot Glass Demo FAQ does state that: "Because of randomness in bond strength, melting doesn’t occur at a specific temperature. Instead, it occurs over a range of temperatures, usually 1100° to 1400° F."
As to what type of sand, that seems to vary based on what type of glass is being manufactured. According to the Schott Guide to Glass, written by Heinz G. Pfaender in 1996, most sand is not of a purity needed for the production of glass since it often contains oxides which color the glass. Plate glass cannot be made from sand with even 0.1% of iron oxide. Quartz sand is used for optical glass and the iron oxide content must be less than .001%. Sodium oxide is usually added to lower the melting temperature of sand (over 1700C).