>So my observation is that beeswax that has been heated for
a long time or at  elevated temps is
much more prone to shrinkage and tunneling in molds.

>Can anyone explain what the variable I am seeing is?  Is there
a scientific  explanation or qualitative
measure that can be used to explain this difference I am seeing?

I can't be specific as to beeswax, but some general rules apply.

I want to point out one oddity, first... You made it sound as if
the shrinkage effect happens, but is delayed, as opposed to
happening normally [excessively] with greater heat. That is odd.
But possible.

Generally I can say 2 things.

1) Some things (chemical actions) occur fast. You/it reaches
a level of voltage or temperature or concentration, and, Voillle'!
ShaBoom! It all comes together.

2) With heat, volatiles emerge. Heat, can be 70F.

Heat and volitiles mean lost mass & "what I will call, buoyancy..."
Density, lost from evaporation of volatiles.

Just thoughts. Slower bonds do seem the stronger, though.
Metals are cooled slowly for strength, and fast, for hardness
which means, [short-lived] brittleness.

Now, a brittle wax, shrinking ANY, would be more apt to
tunnel... eh?  Comments MOST welcome...!
 HNY!
BillSF9c

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