Soda-Lime Glass
Definition
The commonest glass family. About 72 percent SiO2, 14 percent Na2O (from soda ash) and 10 percent CaO (from limestone), with small amounts of MgO and Al2O3. Used in windows, bottles and tableware. Refractive index roughly 1.51 to 1.52.
Related terms
- Borosilicate Glass
- Heat-resistant glass with about 80 percent SiO2 and 13 percent B2O3 (boric oxide). Low thermal expansion. Used in cookware (Borosil, Pyrex) and...
- Concentric Crack
- A crack that runs in roughly circular arcs around the point of impact, joining radial cracks. The 4C rule applies: Concentric cracks...
- Float (Pilkington) Glass
- Sheet glass manufactured on a bath of molten tin. The tin-contact face fluoresces under short-wave UV, which lets the analyst orient a...
- Laminated Glass
- Two glass sheets bonded with a polyvinyl butyral (PVB) interlayer. Cracks but does not shatter. Standard for windshields and bank counters. The...
- Radial Crack
- A crack that runs outward from the point of impact, like spokes of a wheel. The 3R rule applies: Radial cracks have...
- Tempered Glass
- Glass heat-treated to introduce compressive surface stresses and tensile core stresses, producing a material four to five times stronger than annealed glass...
- Wallner Lines and Hackle Marks
- Wavy curved lines (Wallner) and step-like ridges (hackle) on a fracture surface that record the direction the crack front was moving. Used...
Explained in
- Glass: Composition, Types, Fractures and ExaminationThe commonest glass family. About 72 percent SiO2, 14 percent Na2O (from soda ash) and 10 percent CaO (from limestone), with small amounts of MgO and Al2O3. Us...