What resource gathering books have you read besides "Mining for High Quality Granite", if any?1) The gump on the mining tool doesn't reflect what you are set for properly. When set for only stone it still says mining ore.
2) Not sure if the mining part is working as intended. You seem to fail a lot and don't mine up anything, unlike when mining for sand for instance where you always get sand. Seems all you really did was disable getting ore. Not what we really wanted.
There is a base 10% chance to find high quality granite. Previously, while mining for granite you were almost always (since you are at GM mining) guaranteed to dig up metal if you failed to find granite, using up the metal in the resource chunk relatively quickly. Now that you can't mine up metal with the new tool setting you are guaranteed to pull only granite out of the resource chunk, resulting in much higher overall granite yields from a single resource chunk. The success rates have not changed.