Healing Stones

The philosophy of how healing stones work is based on several Asian cultures. More specifically, Hindu and Buddhist practices conceptualize chakras and spend time nurturing, charging, and strengthening these chakras with crystals and stones.
Each stone’s property is specific and they’re associated with different chakra zone colors. “Amethyst, for example, is believed by some to be beneficial for the intestines; green aventurine helps the heart; yellow topaz provides mental clarity. Colors red through violet are associated with seven chakra points on the body.”
The way stones are supposed to work in the spiritual sense is that they conduct the energy requested from it when charged properly. Like I’ve mentioned before, stones can be cleansed by smudging, meditating, placing them out in nature/natural water, or letting them sit under moonlight. These methods cleanse and dispel any previous energies stored in the vessel. 
Scientifically, there’s no tangible evidence of healing stone efficacy. When explaining the effects of this practice psychologically it's described as the placebo effect which is when someone's belief in a treatment effects the outcome. People often discredit spiritual practices based off that.
To me if the mere prospect of incoming healing and prosperity changes someone's outlook, I would call that an effective practice.
I believe that when someone expects a certain outcome, that helps them visualize a positive future. Intentions become reality when positive energy manifests itself.