In this paper, we shall focus on the study of a material, glass, whose use contributes to the conservation of the environment, due to the fact that it forms part of nature itself without any type of manipulation whatsoever, as well as proceeding from a raw material that is naturally abundant. Moreover, it is simple to extract and is not harmful to the environment. Another of its advantages and characteristics is the fact that the manufacturing process of glass containers is similar when virgin raw materials are used as when calcine is employed (from the reutilization of bottles and jars). This second alternative is currently becoming more and more widespread. The recycled material, unlike other materials such as paper and cardboard (Gonza´ lez-Torre & Adenso-Dı´az, 2002), maintains all the initial qualities and may be recycled unlimitedly. As a result, the extraction of natural raw materials is reduced and energy is saved in the manufacturing process of new containers. For this reason, glass has become one of the materials that present the highest recovery rates, with a continuously increasing trend in the number of tons collected (Fig. 1).