Proposal of a new methodology for stone classification in diamond wire cutting technology (EASE-R3) (EASE-R3)

Hardness tests and micro-hardness are currently considered important methods for acquiring useful information about the workability of ornamental stones. For at least thirty years the concept of workability has regarded rock-cutting tools and is the subject of national and international research. This study aims to find a method for the prediction of the behavior of rock-tools using data from easy to use, non-destructive and inexpensive tests. This paper studies 8 stones of different origin classified from 1 to 9 according to an "easy to cut" scale based on the historical company know-how (HIC - Historical Industrial Classification). This was established directly at the marble plant, where stones were cut with diamond wire. The parameters at the basis of this classification are not explicit nor scientifically quantified, because they come from the experience. It was therefore decided to find criteria for the classification of the stones, based on parameters from simple laboratory tests (SSC - Scientific Stone Classification), which lead to a scientific correlation with the industrial classification. For each stone the following investigation techniques were considered: petrographic analysis, higlighting mainly mineralogical composition, crystal size, structure and texture, micro-hardness, ultrasound pulse velocity (UPV). The results of all the performed tests were analyzed and good correlations with the industrial classification were found.