Stones are capable of accumulating both positive and negative energy.
You should always purify crystals before and after using them for protection, healing and amplification.
When you get a new stone, purify it before charging it with your own energy.

By the way, you can also remove all the energies, not necessarily negative, of the people who processed, packaged and sold the stone.

However, if the stone was gifted, you can accept all the love energies that fill the crystal, and rely on your natural protective powers to filter out all that unconscious negative left over from the previous owner.

You should also wash your stones, if you use one, regularly in running water to keep their energies clean.

You should also clean (or demagnetize) those stones that other people have used.
If a person constantly wears a stone, he absorbs the energy of that stone, saturating it with his vibrations.

Stones are best cleaned in the last days of the lunar month, before the new moon, this is due to the fact that the stones under a full moon absorb energy, and the cleaned stone must rest and recover.
After the stone is cleansed and charged by you, it cannot be given to other hands, it will need to be cleansed again.
This is a good time to clean crystals-it is now that I @roxxycrystals them 👍
Do you clean crystals?