Take care of your Yvone Christa piece washing it regularly with mild soap and warm water. You can also use a toothbrush and some bicarbonate to clean deeper.
Please use always a lot of care when handling your filigree jewelry. It's beauty and preciousness lies in the delicate and light craftmanship and should be always handled with care.
Don't expose to perfume, salt water, body cream, hair spray, etc.