Is there such a thing as placing crystals/healing stones in herbs such as Rosemary for added protection?
There is no scientific evidence to suggest that crystals or stones have any healing powers. Controlled experiments have shown that people are as likely to report feeling energy coming from cut glass as from quartz crystals (they are basically the same material, silicon dioxide, except that quartz is crystalline and glass is not). Adding an inert lump of mineral to herbs will have no effect on the herbs, and the herbs will have no effect on the mineral.