The best would be to look at the Mohs Hardness Scale and/or the Rockwell Scale and start at the top and work your way down. The best would be a diamond table top. Tungsten would be the logical choice.

Snark aside, the internet can't help as we don't know your budget, whether this is a DIY venture or a pre-built venture and what meets your definition of neutral and inviting/fits with Japandi.