Wonder if you can cut it with a waterjet, a la slate.
For comparison, a slab of Pennsylvania slate that is 12 inches square (one square foot) and one inch thick weighs 15 lbs. (Slate from other sources can be more or less dense. For example, Vermont slate, from northern VT, is more dense.) So, a slab of PA slate that is 7 ft long by 39" wide (lets say 3 ft, so I don't have to use a calculator) by one inch thick would weigh 315 lbs. By no means do I mean this (the fact that slate is more dense) to infer that slate is "better" than Panzerholz for plinth-building, because in fact I am coming to believe that a combination of these and/or similar materials might be optimal. And it's quite possible that Panzerholz is superior to slate; I haven't tried it. To be honest, the foregoing information about the difficulties of obtaining and working with Panzerholz just shows the wisdom of ordering a finished plinth from Albert.
For comparison, a slab of Pennsylvania slate that is 12 inches square (one square foot) and one inch thick weighs 15 lbs. (Slate from other sources can be more or less dense. For example, Vermont slate, from northern VT, is more dense.) So, a slab of PA slate that is 7 ft long by 39" wide (lets say 3 ft, so I don't have to use a calculator) by one inch thick would weigh 315 lbs. By no means do I mean this (the fact that slate is more dense) to infer that slate is "better" than Panzerholz for plinth-building, because in fact I am coming to believe that a combination of these and/or similar materials might be optimal. And it's quite possible that Panzerholz is superior to slate; I haven't tried it. To be honest, the foregoing information about the difficulties of obtaining and working with Panzerholz just shows the wisdom of ordering a finished plinth from Albert.