[twertsy]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bergy</div><div class="ubbcode-body">Maybe you could post a picture of the thermal image of an actual block stamp. Metallurgically, I guess that the internal stress could impact the heating/cooling rate very slightly. I don't understand why the thermal unit would pick up a stressed area in the absence of heat change though. Worth a try - show us what you have observed. </div></div>

Sorry Bergy, regarding an image of an actual block stamp, we've never done that, but the same principals logically apply. And frankly, an educated guess tells me the people who fake blocks/stampings aren't nearly as careful/skilled as those we are after...