Burying crystals in the earth is a good cleansing method. However, do not use for metal-based crystals such as Tiger’s Eye or Hematite.
Unsuitable for: raw stones, stones in silver, calcite, carnelian, halite, hematite, labradorite/spectrolite, lepidolite, lodestone (magnetite), mica, moldavite, opal, turquoise, ulexite, clusters of most stones.
Smudge sticks of cedar, sage, lavender, juniper, pine or Palo Santo can be used. Pass the crystal through the smoke. The light of candle flame can also be used.
Lemon to purify, juniper to release negative vibrations and lavender to calm and balance crystals used in healing. Mix 2-3 drops of each in a spray bottle of purified water.
Placing crystals in a bowl of dried herbs will also clean them: lavender, sandalwood, rose petals, sage, frankincense, myrrh and peppermint leaves. This takes longer than most methods. Brown rice can also be used to soak up negativity. Do not eat the rice!
If you are attuned you will know that you can reiki almost anything, including crystals.
Chimes, singing bowls and solfeggio sounds for crystals can also be used.
My favourite method of cleansing crystals is with a selenite block. Selenite (described below) is a self cleansing crystal, so I love it for its ease and practicality. I have a large block beside my bed where all my crystal jewellery goes each night. Some recommend quartz or amethyst clusters, personally because these crystals then need cleansing themselves I prefer the selenite method, which I often use with Palo Santo for extra deep cleansing.