Charles, Since this coating is sandwiched between primer and paint,
should I really be concerned about environmental concerns?  I guess
there is the contact between the base and the ground plane, but this is
sealed with an oring or gasket.  Maybe I'm confused by what you mean?

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Shannon Knoepflein   <--->   kycshann@kyol.net

The spec sheet says a 1 mill thick coat achieves 0.25 ohms/sq. This
probably is not much higher at frequency (it's already pretty thin.)
Silver is good, but I think the environmental questions are the key
here. Note, it is "silver plated copper."