About borosilicate glass work:

Borosilicate glass was invented about 300 years ago by a German scientist. He added boron to a traditional glass mix and created a glass with properties ideal for scientific purposes. The glass has a higher melting point than historically traditional glass, and also carries the properties of being much stronger and durable. When worked with heat, the glass remains workable in a taffy or honey like state without dripping off of itself.
Borosilicate glass is the strongest type of glass available, most durable; it also lends itself to be perfect for torch work art glass with a unique color palate of it's own. Color glass is made by adding various metals to clear glass such as gold, silver, cobalt and others. Borosilicate glass needs to be annealed for strength in an oven or kiln at 1050 degrees, then cooled slowly in stages. Pieces are annealed for anywhere between 5 to 30 hours depending on the thickness of the glass.

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