This morning I wanted to check the fertility of my girls first egg plus use the egg for french toast. I cracked it on the side of a pyrex glass pan and uhhh...The egg barely showed a crack. The pan however has a chip...so if you plan on using your goose eggs for cooking don't crack the egg on the side of glass pans. Yeah...I guess she has been hitting the oyster shell harder then I thought. On the plus side the egg was fertile and the french toast was great.