There are multiple ways to refresh your crystals. One of the most common used ways is to charge them in the moonlight. It’s also possible to cleanse your crystal with a small smoke ceremony for example with Palo Santo wood or a Smudge stick.
I would not recommend you to put your jewelry in water, although it might be good for your crystal, it can damage the wirework.
Most metal wires oxidise when in contact with sulphur particles in the air and water. Tarnishing is completely natural. Be sure to have a polishing cloth handy so you can easily restore its shine.
EXTRA CARE TIPS
Store your jewelry in a dark (airtight) place
Avoid water on your jewelry
Allow creams and lotions to dry for at least 5 min before wearing jewelry on your skin
Take your jewelry off before going to bed
Types of wire
Hard plated Silver wire
Copper wire with a silver layer on top. To avoid tarnishing the wire has a clear protective layer on top.
Silver filled wire
Silver wire with a copper inside, the % of silver is higher than Hard Plated Silver.
Sterling Silver 925
This wire is made of 92,5 % silver.
This wire is made out of copper and zinc.
100% copper with a tarnish resistant layer that will avoids corrosion.