Hey John (@john-christian),
I was thinking about your efforts and recommendations to better define the terms of mold, cast, steinkern etc.. I just think that there is some kind of a grey area in all that and that the real meaning will come up with the context. For example do paleontologists still have problems to define a fossil or at least they do it in different ways. Some say a fossil is a remnant of a plant or a animal at least 10000 years old, other think that the structural change within the taphonomic process makes a fossil a fossil. It was also discussed in several forums and the one at researchgate just put it together like this: “fossil” is every bone, imprint, mould, mummified / frozen body, etc. of past living organisms, to the exclusion of those which belonged to still existing populations.”
(https://www.researchgate.net/post/How_old_should_a_bone_imprint_or_mould_be_to_be_classified_as_fossil [accessed Apr 6, 2016].) That is somehow a bit wobbly because they tried to cover every situation.
With our case of mold, cast, steinkern etc. we will end up in a similar way. Everything seems to be debatable and we sometimes might have a hard time to follow one definition for every case. Nature is too complex and we have to decide from a contextual basis.
at the end I really see the benefit for all of us while you are trying to clarify that, because we always should remind ourselves if we use phrases in the correct way.
all the best