Gold retains its lustre over prolonged periods and will not chip, flake or corrode.  It is tarnish-resistant however makeup and cleaning products will dull its appearance.

Silver oxidises over time, turning black when affected by oxygen and light.  To keep your silver tarnish-free frequently polish your silver using a polishing cloth.

Some mild detergent in water will suffice but remember to dry and polish your gold jewellery with a soft polishing cloth after.