Broken Exhaust Stud

For some reason one of my exhaust studs broke in the head I can't believe at 19 ft lbs of torque that would happen. looked to me like it was already cracked. Because it was discolored and a little lighter color were the fresh brake was. I was able to drill it out fairly easily. Bought all new studs and nuts ready to go back together. Any way my question is I bought a new factory metal exhaust gasket from Mazda. I had it torqued up going through the tightening sequence when the bolt snapped. Is it alright to use the gasket over again?