New Synergistic Research Record Mat

Absorption of RFI/EMI has nothing to do with piezo-electrics.    Were one to actually read the references I posted; the posed questions would be addressed.      Of course; comprehension is key!

@cerrot-     Looking forward to your review/experience, one way or the other.      

I am guilty of not reading your citation.  I did goof in a way by saying that the piezoelectric effect in a crystal results in release of RFI; it is the release of electric charge by a crystal under pressure, or applied mechanical stress. I apologize for that error.  But it's only a small boo-boo because the electrical energy released by a piezo material can be of very high frequency, e.g., up to 1 MHz. That's RFI territory.  I wrote not one word about EMI, by the way.

I like that paper from 2016.  That would support the utility of a crystal in this application. 

The tech does open the door for a wide range of possibilities, when it comes to electrodynamics.    Given radio frequencies are part of the EM spectrum; I tend to lump them together.      Perhaps: not that good an idea, when it comes to clarity.                                                              Happy holidays and listening!