Placing turntable on top of fireplace mantle?

I think an easy test for potential turntable placement is to place half a glass of water in the intended spot and walk around the area.  The water should remain almost perfectly still.  If it wobbles, pick someplace else. Now, the stuff about the corners and the heat is another story.  

How about just put the freakin' turntable there and listen to some music? (No disrespect intended, Chayro.)
Or, you could hit it with a hammer, pour water on it, wait for 100 mph winds to blow across your chimney, light a roaring fire and feed it with gasoline. (I must be in a bad mood.  Sorry.)

(I must be in a bad mood. Sorry.)

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Yup...No gas ay. :-).
I can see the vinyl running, as I think, I think!

Ok then let me encourage you do it. Forget the reason.. All is good.
It will "Look" good there.  I wish you  the best, won't make it the best.

Again do you use the fire place? It makes a difference.. If heat and bass control isn't an issue.  You know the stuff that makes the stylus BOUNCE.. GOOD! You did something I couldn't.. If I hadn't tried something real close I wouldn't comment.. But I did..

Didn't work for me, with HUGE industrials, or my Thoren 124s/121s

They are not as picky as your TT, I assure you... The Russco's are pure boogie brother...They are made to party around the table, really...HD MM carts, just for broadcasting and station vinyl. TOUGH!!!

Ya never know though.. You may have jumped on a magic carpet, and get the best sound of your life..

Regards

@lewm - no disrespect to you either, but IMO it's alot easier to check and see if an area is vibration-prone before setting up the table and doing the wiring only to find out the arm is going off the rails every time you move.  But that's me.  We're all in a bad mood sometimes.  Especially now. 

Looks solid. You may need springs later.

The only major thing is corner placement on it's on can be problematic.