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Due to the commonly higher compaction intensities and higher lateral pressure in the mold and the associated lower degree of humidity in the molding material, this phenomenon often occurs when demolding bentonite-bound mold materials. This phenomenon is caused by tensions in the mold resulting in increased elastic properties of the bentonite-bound mold material. In the worst case, the bridging bonds are torn open reducing the tensile strength in demolding direction which finally results in mold breakage. 

The so-named Shatter index is a characteristic value describing the plastic properties of a mold material under dynamic stresses.