raw material:
quartz sand, lead oxide, sodium and potassium |  | furnace containing liquid lead crystal, at a working temperature of 1100°C/2012F | | first step to produce the bowl; glass bulb (gather) on hollow metal rod
(blow-pipe) | | liquid glass pre-moulded
in a shaping block | | prior to blowing into the mould | | mouth-blowing by using the blow-pipe |
