Dear Bill,

A good technique to observe changes in calcite or aragonite crystal
structures and small compositional changes is by use of cathode luminisence
(CL) techniques, which is done on thin sections. OK, you need specific
tools for that, but I am certain there are some labs around who can help
you with that. Maybe there are some on this list who can suggest a good
nearby place for you!

About your statement on the ark and titanic: You're right with the ark,
they were amateurs and produced something new and even got it published -
try that nowadays...... Even to get published a new design as was the
Titanic might give problems to publish. But I support your vision - if
nobody tries new things we come to a standstill, don't we? I just wanted to
put my finger on this small fact most of you will recognize.

Pier de Groot

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