A bearing to provide a constrained relative motion between a first member and a second member, said bearing including: an elastomeric mold bonded bearing stack, said elastomeric mold bonded bearing stack including at least a first nonelastomeric member layer and at least a second nonelastomeric member layer, at least a first mold bonded elastomeric shim layer, said at least first mold bonded elastomeric shim layer having an exterior surface and an interior center distal from said exterior surface, said at least first mold bonded elastomeric shim layer positioned between said at least a first nonelastomeric member layer and at least a second nonelastomeric member layer, wherein said elastomeric shim layer comprises an enclosed interior elastomer region distal from said exterior surface, said interior elastomer region comprising an interior cured elastomer composition having at least a first interior optical characteristic ingredient, characterized in that said elastomeric shim layer comprises an exterior elastomer region encompassing said interior elastomer region, said exterior elastomer region proximate said exterior surface, said exterior elastomer region comprising an exterior cured elastomer composition having at least a second exterior optical characteristic ingredient, said at least second exterior optical characteristic ingredient different than said interior cured elastomer composition first interior optical characteristic ingredient, wherein an elastomer void crack propagating from said exterior surface inward towards said interior elastomer region, the bearing being configured such that a repeated relative motion between said first member and said second member generates a plurality of interior cured elastomer composition crumbs to be expelled from said elastomer void crack towards the exterior elastomer region, said interior cured elastomer composition crumbs optically distinguishable from said exterior cured elastomer composition, said interior elastomer region optical characteristic ingredient difference providing a visual crack depth determination. an elastomeric mold bonded bearing stack, said elastomeric mold bonded bearing stack including at least a first nonelastomeric member layer and at least a second nonelastomeric member layer, at least a first mold bonded elastomeric shim layer, said at least first mold bonded elastomeric shim layer having an exterior surface and an interior center distal from said exterior surface, said at least first mold bonded elastomeric shim layer positioned between said at least a first nonelastomeric member layer and at least a second nonelastomeric member layer, wherein said elastomeric shim layer comprises an enclosed interior elastomer region distal from said exterior surface, said interior elastomer region comprising an interior cured elastomer composition having at least a first interior optical characteristic ingredient, characterized in that said elastomeric shim layer comprises an exterior elastomer region encompassing said interior elastomer region, said exterior elastomer region proximate said exterior surface, said exterior elastomer region comprising an exterior cured elastomer composition having at least a second exterior optical characteristic ingredient, said at least second exterior optical characteristic ingredient different than said interior cured elastomer composition first interior optical characteristic ingredient, wherein an elastomer void crack propagating from said exterior surface inward towards said interior elastomer region, the bearing being configured such that a repeated relative motion between said first member and said second member generates a plurality of interior cured elastomer composition crumbs to be expelled from said elastomer void crack towards the exterior elastomer region, said interior cured elastomer composition crumbs optically distinguishable from said exterior cured elastomer composition, said interior elastomer region optical characteristic ingredient difference providing a visual crack depth determination.