can someone explain the volume formula and how that is used?
(Sorry for the clumsy wordage – I don’t want to fool with html for the superscripts.)
“Volume divided by width cubed = N” is used to estimate the finished weight of a stone. So, Volume = N*width cubed. Cube W (in cm), multiply by N, then multiply by the specific gravity of the material. This gives you the estimated weight in grams.