The Bregenzer is not broken
The medium grit Bregenzer whetstones are hand quarried, and so show natural irregularities. Though they may appear irregular and chipped, they are, in fact, smooth where they need to be. The narrow edges are the faces that will contact your blade. These should be smooth, and they taper roughly at each end (not perfect points). The broad sides are where you hold the stone. The roughness of these broad sides will allow you to maintain better grip while honing and sharpening.
Occasionally stones do break in transit, so if you have received a broken stone, please be in touch.