What is Glass?: An Introduction to the Physics and Chemistry of Silicate Glasses

Abstract

This chapter presents the glasses form the point of view of their physical and chemical characteristics and focuses in silicate glasses, the most common compositions concerning archaeological and historical glasses. Besides the fundamentals of the glassy state, which includes the concept of transition temperature and the criteria on the formation of glasses, a brief and explanatory view of the structure of the glassy random network for silicate glasses is given. The second part of the chapter is devoted to properties of glasses. Among them, those directly connected with archaeological and historical glasses have been described: thermal expansion, viscosity, elasticity modulus, mechanical fracture, toughness, refraction index, brightness, optical transmission, etc. Special attention is given to chemical resistance of glasses against different aqueous or humid media: acid, basic and neutral to which historical glasses have been commonly subjected.