Glass failure analysis expert witness performs a failure analysis on a hollow glass tube that failed due to internal pressure. The glass fracture initiated at a small bruise on the outer surface of the glass tube. The upper left 25X photomicrograph gives an overview of the failure. One can see that the glass fracture analysis determined that the failure initiated at a small bruise. The upper right 100X photomicrograph gives more detail of the origin. This was a manufacturing defect because the bruise was created during manufacturing.