How diamond can be cut?
Diamonds have been cut for hundreds of years, while lasers have only been around 50. The simplest method of cutting a diamond is to take advantage of diamond’s unusual structure. Diamond has “grain”, just like wood. Where wood has darker and lighter lines running through it, diamond has “zones” of decreased hardness. If you take a diamond and cement it to a rod, then place the edge of the stone against a flat steel wheel which has a paste containing diamond dust in it, then while the disc is spinning, some of the diamond dust with harder “zones” will rub against the secured stone’s “softer” zones and slowly (very very slowly… it may take days to cut through a diamond) you will cut it in half. In these modern days, there are actually materials harder than diamond, but they are not used to cut diamond, perhaps someday, though.
