Well, for a start, Aqua, Herbalism has nothing to do with stones.It is the study, and use, of plants. (All plants are herbs,we only distinguish "Herbs" from other plants for cooking.)
In witchcraft herbs are usually used for healing. Every medicine used by the Medical Profession came from plants. Even the ones now manufactured artificially originally came from plants; a great many from the Amazon jungle!
Stones are used for other purposes.