seki shop talk

Hey Chris got a question for you!
It's kind of tricky for Halloween...
Was troubled by, "water retention and slow evaporation"

I have been though to collect the hardest material possible when looking for suiseki.
According to the hardness scale, But these stone of mine do not hold water on their surface.
Jasper's, serpentine's and jade's which I prefer.
It runs right off or at best beads slightly,
Can you please clarify which is more important...