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Soda–lime glass (for containers) [2] Borosilicate (low expansion, similar to Pyrex, Duran) Glass wool (for thermal insulation) Special optical glass (similar to Lead crystal) Fused silica Germania glass Germanium selenide glass Chemical composition, wt% 74 SiO 2, 13 Na 2 O, 10.5 CaO, 1.3 Al 2 O 3, 0.3 K 2 O, 0.2 SO 3, 0.2 MgO, 0.01 TiO 2, 0. ...
Glass can be coloured by adding metal salts or painted and printed with vitreous enamels, leading to its use in stained glass windows and other glass art objects. The refractive, reflective and transmission properties of glass make glass suitable for manufacturing optical lenses, prisms, and optoelectronics materials.
Chemical strengthening results in a strengthening similar to toughened glass. However, the process does not use extreme variations of temperature and therefore chemically strengthened glass has little or no bow or warp, optical distortion, or strain pattern. This differs from toughened glass, in which slender pieces can be significantly bowed.
Physical changes occur when objects or substances undergo a change that does not change their chemical composition. This contrasts with the concept of chemical change in which the composition of a substance changes or one or more substances combine or break up to form new substances. In general a physical change is reversible using physical means.
There are four basic types of commercial silica glass: Type I is produced by induction melting natural quartz in a vacuum or an inert atmosphere. Type II is produced by fusing quartz crystal powder in a high-temperature flame. Type III is produced by burning SiCl 4 in a hydrogen-oxygen flame.
The glass transition of a liquid to a solid-like state may occur with either cooling or compression. [10] The transition comprises a smooth increase in the viscosity of a material by as much as 17 orders of magnitude within a temperature range of 500 K without any pronounced change in material structure. [11]
Following the atomic bombing of Hiroshima, it was discovered in 2016 that between 0.6% and 2.5% of sand on local beaches was fused glass spheres formed during the bombing. Like trinitite, the glass contains material from the local environment, including materials from buildings destroyed in the attack. The material has been called hiroshimaite ...
Vitrified sand is a type of natural glass, contrasted with manufactured glass in which soda ash or potash are added to lower the melting point. Pure quartz melts at 1,650 °C (3,002 °F). There are several natural processes that produce more or less melted sand and one man-made form: Fulgurite is sand fused by a lightning bolt hitting sand.