Sorry - I've read all the old threads about how much pumice to add, but I want to ask again. The pumice powder I have is very fine. I want to make a 'foot scrubby' soap. I see that @IrishLass recommends 2 tablespoons PPO, which is what I'm tending towards. I think any less than that wouldn't be scrubby enough. It is not intended that I use the soap all over my body - just on my feet as one would with a piece of pumice. And/or maybe as a gardeners soap as a second option? Could I use even more than 2 Tb PPO or do you think it would make the bar too crumbly? TIA.