SCIENCE in ART Step 37 Gallery ©  2010 The American Scientific Glassblowers Society All Rights Reserved click to enlarge 80.6%  [SiO2] _ 12.6% [B2O3]      4.2% [Na2O] _ 2.2% [Al2O3] _ 0.04% [Fe2O3] _ 0.10% [CaO] _0.05% [MgO] _ 0.10% [Cl] borosilicate glass FUSION great hands