Most jewelries will have wear and tear, yep even solid gold too (yes, even the ones that cost $250). Decolourize / fading will occur under specific circumstances (if you have a more acidic physique) but ultimately, it boils down to how you take care of it.
Keep your jewels shining with these care steps:
1. Keep away from water
2. Avoid contact with perfume, lotion and other chemicals
3. Store in a cool, dry place