GDD Forets pour Granit – Perceuse | Humide | M16 (1,5)

hello Chris,
Do you use the drill bit with an angle grinder?

RPM:
max 6000 (up to 12mm diameter)
max 400 for the bit 14mm-diameter and the bigger ones.
About the feed rate, there isn't a parameter because you go manually, slowly putting pressure on the material. 
do not go into the material perpendicularly but use the tool by tilting and swinging while cutting.
As you know quartzite is the most hard material in nature, so be careful and go down slowly.
Use the water to help the diamond tool.