Crystals and gemstones have been used for healing for hundreds of years. It was common for people living during the times of the Roman Empire to use gemstones as amulets and talismans. Roman doctors used crystals for medical treatment and soldiers even carried Tiger's Eye to provide protection in battle. While gemstones stand the test of time, their healing energies do not.
When you utilize crystals and gemstones for energy work, healing, magick, and other purposes, the metaphysical energies they possess can be depleted or polluted. As a result, negative or stagnant energies can replace the crystal's original healing properties.
In order to keep your crystal's original healing vibes pure, you'll need to charge them after every use.
The easiest way to charge your crystals is to place them on or near Selenite. Selenite is used to cleanse and charge crystals because it has the powerful metaphysical property of being able to charge itself.
Leave your crystals on or near Selenite overnight to recharge and cleanse them back to their original metaphysical power.
The Full Moon
In my opinion, the full moon has the most powerful energies for cleansing and charging your collection of crystals.
Below are very simple instructions on how your crystals can utilize the moon's powers.
Collect all the crystals you want to be cleansed and recharged. On the evening of the full moon, rinse all your crystals under running, clean water.
Once your crystals have dried, place them in a bowl and set it on window sill or outside where the light of the full moon can shine down on them. For best results, allow your crystals to remain in the moon's light until it sets in the west.
If you'd like to add a step to this process, perform a Full Moon Ritual by setting an intention for each stone placed under the moonlight. The full moon is about releasing all that no longer serves you. Giving each of your crystals an intention will charge them with the power they'll need to assist you in releasing the old to bring in the new.
Just as the full moon can charge crystals, the power of the sun can too. I personally do not use the sun to charge my crystals because it can fade the color of photosensitive crystals like Amethyst, Fluorite, Celestite, and Rose Quartz.
However, if you feel your crystals need a quick charge, wash them under clean, running water, place them in a bowl, and sit them in a windowsill for a couple of hours.