Turntable Mats: Rubber, Felt or Cork.


I have a Linn Basik Turntable with an Akito tonearm and Rega Exacta 2 cartridge. Would one expect a noticeable sonic difference when changing from a felt mat to a rubber and cork mat?
joscow
Here are the mechanical requirements for a good mat:
It must have the same hardness (durometer) as the LP, so vibration from the LP can be absorbed (without reflection) and converted to heat. To this end it will affect tonality if too hard or too soft.

It must support the LP properly, at the vinyl depresses at the location of the stylus where the pressure is extreme.

It should also be effective at damping the platter! When the stylus tracks the groove, the vinyl can 'talk back' which is why it has to be controlled. But the platter can editorialize too, due to room-borne vibration. It has to be dead.


If the platter pad is working correctly, you may notice that with the volume off the stylus tracking in the groove is silent.


This is a lot to do- but the results of this are obvious- a properly designed platter pad can cause a cheap turntable to have better tonality than an expensive one. The platter pad is a critical part of LP playback!
So atmasphere, the obvious question for us non-scientists.  What material(s) have the same, or very similar, hardness as a typical vinyl LP?

From your comments that would be the place to start when considering mats.
What material(s) have the same, or very similar, hardness as a typical vinyl LP?
To my mind the obvious place to start would be similar to Noromance and myself have already done.
An album, be it a vinyl 10" or a shellac 78 as a mat.
Well worth a trial IMHO.
Many years ago when I was trying different mats on an old Rotel RP 850 I concluded that the best mat was another LP!  Are there vinyl mats out there?