Jerry, you've been off with your cracks explanations from the start.

You said in one of the threads that it clearly was a stress crack. Now according to your theory, it should have been an impact crack. Stress cracks are related with elastic and plastic behaviour, in the end followed by necking and eventually the crack. Under cyclic loads, cracks go through an initiation and propagation phase, untill the residual strength is too low to hold the stress load.

Impact cracks behave totally different from stress cracks. A metallurgist knows that. That is, for metals. I don't know what a metallurgist knows about mud cracking open.

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To the regular visitor of internet bulletin boards it is clear that it's an excellent idea your parents get to choose your real name.