Each of the different stages that have to be covered until a finished product is achieved, and that can be summarized schematically in the attached table, bring about a series of techniques and regulations in order to reach a perfect commercialization of ornamental rocks.
Thus, in the locations and determination stages of a stone quarry, and once the beauty of the stone has been determined, we must define the degree to which it can be quarried by means of setting a series of factors, some measurable and others less objective.
After having defined “the quarry degree” of a product, it is necessary to define its quality. In this sense, the concept of quality is intimately tied to the concept of security.
The European Commission, in order to achieve the common market, has developed a series of directives for technical requirements coordination in natural stone products. One of these was directive 89/106/cee of the council of 21st December 1988. Later, it was modified by a series of dispositions, the main of these being the directive 93/68/CEE of the council of 22nd July 1993, concerning the branding CE.
The development of the directive consisted in the elaboration of technique rules by the Normalization European Committee (CEN). In the case of natural stone, there were four technical committees that dealt with the normalization of building products:
- CEN/TC 125: bricklaying
- CEN/TC 128: products of discontinuous collocation for roods and wall coating
- CEN/TC 178: united for pavements and kerbs
- CEN/TC 246: natural stone
The activities of these committees consisted in the composition of product rules. In Spain, the publication of these rules has been done by AENOR, which approved the Regulations of the Infrastructure for Industrial Quality and Security in Spain.