The five qualities of crystal - memory, storage, expansion, transformation, focus.
Just bought crystal, due to the crystal will remember all what it contact with things, so it is possible that a crystal original stone retains the mining workers, miners, traders, carved by the porters, retailers, or the memory of the master, and so on. Some bad memories may even affect the owner of the crystal. So purify it.
Crystal is worn long, or use crystal therapy, easy attract negative performance quantity, so also want to make crystal clear oh, also have person to demagnetize method, can restore original magnetic field. Generally speaking, the purification time is about 1 month. If it is used for medical treatment, it should be cleaned once a week. Also, when the crystal feels sticky, remember to clean it up quickly.
Sun purification method: using the direct sunlight, preferably in the morning to noon sunlight is the most appropriate, about 2 hours if not carefully over time and it doesn't matter, but must be back before sunset. Amethyst and silt are not suitable, will fade.