Hey Jack @jkallmeyer, that is a very impressive tool and your home lab is very well equipped, respect for that. Your saw reminds me of the saw I was using at the stone prep lab at the University of Leipzig, even if we had some more safety features and regulations (like plexiglas shield etc.) and cutting free hand was a no go 😉 I always had to fix the stones (it took ages) on a slide with automatic propulsion. That way the cut was always straight and smooth and no chance to ruin the blade. The blade diameter was almost 20 inch (50 cm) and I had another monster saw with a huge motor and a 30 inch blade for big blocks. The speed of the smaller one was stepless adjustable and best for cutting all kind of stones (soft and very hard), even agate. For polish I used cilicium carbid powder or Coferpol polish powder (mixture from Al2O3 , Cr2O3 , SiO2) on a glass plate. And then looping with not to much pressure till the agate shines 😉
We also let kids polish agates at special family museum events. First we cut the agate nuggets, then we glued them back together with hot glue. The kids had to split the nuggets and polish them with the powder. After finishing they could take the shiny agates as a gift home and their parents could give us a donation if they like. That was always a lot of fun.