You've Asked, And we did our research on many methods of cleansing and charging crystals.
Please use this method as informational purpose.
A lot of minerals can and cannot withstand some of these methods. At Rock Collage, we do hold Crystal 101 classes to help differentiate the ones that can and cannot.
METHODS OF ENERGETICALLY CLEANSING A CRYSTAL
Method
Information
Basis
Sunlight
Place crystals in sunlight for no more than half an hour. Sunlight breaks down negative ions. No crystal will fade or be damaged from only half an hour in the sun.
Proven
Sound
Use a singing bowl or chimes/bells/tuning fork and strike it directly next to a crystal. Be aware that the sound emitted must be of a higher frequency than the crystal you are trying to cleanse.
Proven
Salt Water
Place crystals in a bowl of salt water for a few hours. The salt water will absorb any negative ions. Natural sea salt or Himalyan salt is preferable to white, processed salt. Remove crystals, wash them off in clean, fresh water and dry them. Do not use salt with porous, water based or metal based crystals (ie. opal, lapis lazuli, malachite, hematite etc.) If in doubt, do not use salt.
Proven
Dry Salt
Place crystals in a bowl of dry sea salt for a few hours. Bury the crystals deep in the salt. The salt will absorb any negative ions. Discard salt afterwards. Do not use salt with porous, water based or metal based crystals (ie. opal, lapis lazuli, malachite, hematite etc.) If in doubt, do not use salt.
Proven
Water
Wash crystals under running water, preferably the fresh water of a stream, river or waterfall, but under a tap is just fine too. This method will not necessarily clean a crystal energetically & remove the negative ions, but it will physically clean a crystal. A soft toothbrush can be used to clean a cluster. Do not use water on crystals softer than 4 on the hardness scale. Crystals such as Selenite will dissolve in water. If in doubt, do not use water.
Proven
Reiki
Reiki energy is strong as it is universal energy channeled with intent. Firstly, place your hand above the crystal, activate your energy and say 'cleanse'. Wait until the energy lessens a little and then ask it to 'charge'. Wait until the energy lessens again and know that the crystal is now cleansed & charged. Unfortunately, this method cannot be proved, but I have found it works quite well.
Unproven
Smudging
Light sage, Cedar wood, Sweet grass or Sandalwood and waft the smoke over and around the crystal, passing the crystal through the smoke several times. Ask in your mind that the crystal be cleansed and know that it is so.
Unproven
Earth
Burying a crystal in the earth for a few days or weeks will ensure all of the negative ions drain out of the crystal and into the earth. See above information regarding salt & water (which is present in a lot of earth).
Unproven
METHODS OF CHARGING A CRYSTAL
Method
Information
Basis
Sunlight
Place crystals in sunlight for no more than half an hour. Sunlight breaks down negative ions. No crystal will fade or be damaged from only half an hour in the sun. This method can be used to both cleanse AND charge a crystal. It is the easiest & most cost effective method to use. Just pop your crystals on a windowsill or outside if you prefer.
Proven
Crystal Cluster
Large clusters of crystals can be cleansed, charged and then programmed with the intent to 'energise'. If we then place smaller crystals (of a lower vibration) such as tumble stones or pieces of jewellery on to the cluster, the smaller pieces will absorb the energy of the larger piece and will become charged. The larger cluster must be cleansed and recharged after each use. Amethyst, Clear Quartz, Kyanite & Selenite are all excellent energizers.
Proven
Reiki
Reiki energy will charge up a cleansed crystal. Place the crystal on a table, hold your hand over the top of it and send reiki into the crystal with the intent that the energy will Charge. The crystal be filled with universal energy. I charge all of my crystals in sunlight AND then reiki them too for good measure 🙂
Unproven
Moonlight
Place your crystals under the light of a full moon and they will be charged. Please be aware that the moon's effect on the earth is magnetic. The light from the moon is so weak, it cannot charge up a crystal. However, many people strongly believe that it does, even though there is no evidence of such.
Unproven
Running Water
Wash crystals under running water, preferably the fresh water of a stream, river or waterfall, but under a tap is fine too. This method will not necessarily clean a crystal energetically & remove the negative ions, but it will physically clean a crystal. If the crystal is of a lower vibration, then running water may both cleanse and charge it.
Unproven
Earth
Burying a crystal in the earth for a few days or weeks will ensure all of the negative ions are drained out of the crystal and into the earth. The earth is then said to recharge the crystal.
Unproven
Resource: