In this paper, a new method of measurement of brittleness of glasses is first discussed. Vickers indentation is employed in the new method and the ratio of median crack length (C) and indentation diagonal (a) is used to estimate the brittleness. This method allowed a quick glass-compositional survey and a new less brittle glass in the soda-lime-silica glass family was developed with brittleness 5.1um-1/2 as compared with the brittleness of 7.1um-1/2 for commercial soda lime glass. The crack-initiation load of this new glass was 10 times higher that the soda-lime glass. In order to understand brittleness itself, several properties of glass were studied and compared with brittleness. It was found that for the normal glasses, the density showed a good relationship. For these glasses the brittleness decreased with decreasing density.
