Diamond Spar. 95 Ufe. ^°th diamond fpar and corundum are employed in Cutt ing and policing hard minerals. Obfcrvations. r *• The great hardnefs of corundum and diamond ^ independent of their ftrong affinity to fapphire, jj. a y he confidered as juftifying their removal to the nt genus. °nl' com P a< ^ : corundum of Bournon is probably ^ a variety of the following fpecies. Of * 1 * s probable that diamond fpar is only a variety , u hfpecies of corundum. FIFTEENTH