Many crystals LOVE to be cleansed. It is best to get advice from someone knowledgable about crystals before cleansing your crystal companions so you don't damage them ( for example: some love rain, some would be ruined by rain).
When I have heaps of small crystals for use in crystal infusions, or landscaping and home blessing, I create what I call a sage double-boiler. No, I don't heat them! I put them in a sieve over a pile of smoky sage. They love it!
But my absolute favorite way to clear crystals is with sound. Place smaller crystals in a singing bowl. For larger crystals I take advantage of the best massive vibrations I know of - thunderstorms! I place crystals in an open window-sill during thunderstorms. My experience is that crystals love thunder. As a person who is sensitive to barometric pressure, I can relate. That first crack of thunder usually means relief from pressure.
If you have any questions about care and clearing of crystals, send me a message!
Love,
Emelie