This is called diversification, and you can learn more here. This can happen from it being worked too much. We think this happens because some of the sodium has been lost. It can also happen from it cooling to fast on the skin and not on the inside, but this type can be fire-polished. If the hazy comes from overworking, the glass is ruined.
Bangers tend to get hazy or chazed when a user torches the quartz too hot with too much carbon in the banger. The carbon will start to bond to the quartz, causing the chaze