Hi,
I recently posted a question about grinding some green limestone.  Thanks all for the input.  I did an extensive test and it found that I had to go to 50 metals to get the overall damage out, and had to go down to 30 grit to get the really badly damaged stuff corrected.  I have a few related questions:
1. Does anyone have a recommendation for a good aggressive metal diamond that I can use on the limestone?  I have been using some old metals that work fine on concrete, but if there is something out there that is a little more aggressive or effective in order to eliminate some of the grinding time, that would be great.  Someone recommended some vitreous diamonds a while back, but I'm not sure what that is. 
2. when transitioning from metals to resins I have gone to 200 metals and then back down to 100 resin, and I have also gone to 100 metals and then back down to 50 resin.  Would there be an advantage to one method over another?
3. I have a klindex machine with a planetary device that I use for grinding concrete but have never had to use it for grinding stone.  Was wondering if the planetary would improve the efficiency of the job or overall finish of the stone.  The cups on the planetary keep the metals in place so the diamonds are not thrown on concrete, but I haven't run into that problem so much on stone.
3.To achieve a satin finish I tested the diamonds up to 200 and then used an 800 twister/spinflex type pad and it gave the finish a low satin finish.  But to get more shine without many more steps, what would work?  I am concerned about using polish because in the past I have had a hard time adjusting the level of gloss.
Thanks for your input!
Baird