I'm a Dummy, Tell Me About Turntable Mats

Depends on the table.  I haven't used a mat sine the AR table days.  Been using a VPI table since the early 90's with no mat.  That said, record clamps or weights need to be used if no mat.  

At least that's what works for me.

A little off-topic, but I always found it interesting (curious??) that VPI does not endorse TT mats on their tables.   Last table I bought shipped without one; when I reached out to them for one, they kind of tried to “talk me out of” needing one.   But in the end, they will send upon request.    Just a little weird, IMO.   

Jim

Oyaide br-12 is a very nice mat . 
If you find one..

I use a Stein music mat on my MMf-7.3...it is a super thin mat and causes no issue with VTA. To me, it sounds great...it ought to at $249!
Also have the Origin Live mat, but have not used it yet. I  originally had, actually still have, the original Ring Mat. It is also a great mat imo. Lastly, I have several leather/suede mats from Hide in the sound, they are a nice economical mat.
On my Technics mk7, I am using a KabUSA glass platter mat combined with a technics thin rubber mat...also have a Herbies mat for this table.

I purchased a Clearaudio Ovation on the used market. The platter had some minor cosmetic damage so I purchased the Oracle mat which has has an adhesive to place over the Ovation platter instead of purchasing a new Ovation platter (3x the Oracle price) very happy with the outcome.