The main gems reflecting cosmic light used in this process are: Ruby (red), Pearl (orange), Coral (yellow), Emerald (green), Moonstone (blue), Diamond (indigo) and Sapphire (violet).
By utilising the seven gems (used in Ayurvedic medicine) an experienced radiesthesist would be able to determine the colour weakness, using a body specimen, such as a nail sample - by dowsing. This sample retains its energy connection with the person from whom it was taken. By holding the sample and a pendulum a response would be witnessed when swinging the pendulum towards gems placed in an arc in front of the practitioner. The nail/pendulum would be electro-magnetically attracted to gems that resonate with the required frequency of the specimen.
The colour vibrational resonance of gems and remedies can be determined in a similar way.
The pendulum oscillating towards the bottle containing sapphire would indicate an inability to efficiently absorb the violet part of the solar spectrum.
The next step would be to refer to the case notes and cosmic colour files to search for an appropriate remedy and one that resonates with violet.
With this approach the practitioner would be in a position to influence health changes by 'tracking' the cosmic colour deficiencies as the body displays symptom changes.