This shouldn't be in herbalism. I think magical items would be more appropriate.
Granite to some is a sacred and powerful stone good for protection and abundance. It is good for diplomacy, and increasing co-operation. It is great for balancing out any type of relationship; especially that of with friends.
Granite helps us to look at the bigger picture. Great for making you see opportunities. It is also used for grounding, and getting rid of negative energy.
The chakras it is associated with are the root and sacral chakra, so it can help with them.