Jewellery pieces containing multiple kinds of stones generally do not work for healing as their different energies usually cancel each other out, and so most jewelry suitable for healing contain only one kind of stone. Jewellery pieces with multiple stones can be used for healing as long as the stones are all the same kind, for example: a ring with several rubies or a bracelet of amethyst beads.
However, jewellery with two different kinds of stones will work if one of the stones is transparent and colorless, such as clear quartz or diamond. In this instance, the clear stone will serve to amplify the healing effects of the other stone.
Sometimes, jewellery containing multiple varieties of stone (usually only two or three) might work for healing if the stones’ energies harmonize well with each other (ie. they have very similar healing properties). Usually, however, different stones are put in the same piece of jewellery because they look good together, not because their energies harmonize.
Several different stones and crystals can be worn for healing at the same time as long as they are in separate jewellery pieces that do not touch each other. To use your jewellery for healing, you would do the same with it as you would with any other healing stone (ie. cleanse it, charge it, program it, etc.). Smudging is the best method for cleansing the energy of your jewellery as other methods may damage it. You should cleanse and recharge your jewellery after each use, or, if it is worn regularly, it should be done daily.