Quality index for ornamental slate deposits

A methodology for exploitation of ornamental slate deposits was developed from data obtained from borehole exploration. The method begins with the definition of geological, geotechnical and aesthetic parameters that determine the quality of the slate deposit. Then a collection of data from continuous sampling exploration was carried out in order to propose a quality index through multivariate statistical techniques that integrate all variables. This quality index is considered as a regional variable and, by geostatistical methods, its value was extrapolated for each sample from surface exposures and boreholes. This allows quantification of the quality of the deposit.