The only way I can figure to find out is to happen upon the correct pattern (an enclosed 3X3 grid with the middle spot necessarily being mine free) and I’ve never done it.
Anyone? Yellow? Orange? White?
I think it’s greyish. I know that I’ve seen it before, but it’s been a while.
Or it might be that 8 is black, and 7 is greyish.
Just for reference:
1 is light blue.
2 is green.
3 is red.
4 is dark blue.
5 is brown.
6 is aqua.
Wait. No, 7 is black, right? I’m pretty sure that’s correct.
Man, this redefines MPSIMS, I’ll tell ya. 
You where right the first time. & is black and 8 is light grey. Created a custom game 9x9 with 64 mimes. Didn’t take long to find an 8.
That should be 7 is black.
Yep. That took about 4 tries, and up popped an 8! Light grey, as advertised.
And thanks, guys, for satisfying my thoroughly M and P curiosity about this.
So you were pretty much trapped in an invisible box, huh?
[Marcell Marceau in silent movie
Non
[/MarcelMarceau
Good thing he found that rope.