You can, of course, try to cut a glass cutter or an angle grinder, but even with a slight deviation from an even mowing line, it will begin to crumble.
Ungakwazi Ngokuqinisekile uzame ukusika ingilazi ingilazi umsiki noma grinder, kodwa ngisho ukuphambuka encane evela umugqa flat, izoqala ukuwa.