Ostrea earrings are made of durable, artist-grade polymer clay. However, they are pieces of handmade art and should be treated as such.
For the longevity of your earrings, I recommend removing them when doing the following:
applying lotions, oils, perfumes, sprays or aerosol products
If makeup gets on your earrings, it can be gently removed using a makeup wipe, baby wipe, or q-tip dipped in water. Rubbing alcohol or acetone can remove stubborn stains, but only use these on earrings that do not have any surface treatments (resin, gloss). For earrings with resin, avoid prolonged exposure to direct sunlight as this may cause discoloration.
I recommend storing your earrings in a jewelry box or soft bag, away from other jewelry.