Robert Gammon wrote:
...

I have done an experiment with a tumbled surface travertine sample. The
surface had NO visible unfilled areas. Got the stone VERY wet, put it
down on carpet and put my foot on it and PUSHED, The stone slipped on
the carpet before my foot skidded off the surface.


In other words it is not slippery to the feet even when wet.
I may misunderstand but I thought that what they called tumbled usually
came with an unfilled surface
I will look further into marble master.
Thanks

..
All travertine has voids in it, you pay for the fewest number and
smallest number of voids. www.marblemaster.com even explains the
difference and prices the quality levels differently.

Best Quality 18inch brushed travertine from MarbleMaster goes for $4.39
sq/Ft and shipping is free if 2000 Sq Ft or more are in the order.
OTOH, it is a freight shipment, and YOU are responsible for having a
suitable forklift available to unload the pallets (3240 lbs for 360 sq
ft. - each 7/16 inch thick tile weighs 14 pounds).