Abstract
A new practical method is presented for estimating the volumes and masses of quarried stones from their projected areas and is compared with two conventional methods based on the intermediate axis and three characteristic dimensions. The projected areas are obtained from two horizontal orthogonal images of the stones taken by a camera with the aid of a measuring frame. The parameter of each prediction equation for the new method and the two conventional methods was fitted to data obtained from a sample of 100 small crushed stones. The results indicate that the new method is the most accurate and precise, with a range of -23% to 30% in relative error for 95% prediction intervals. Full-scale validation using large quarried stones of 1.16 to 3.01 tons showed that the new method successfully predicted the masses of quarried stones within the accuracy range expected from regression analysis, while the method that relies solely on the three characteristic dimensions resulted in predictions that were beyond the acceptable range of error.
