Both silver and gold are quite soft metals so expect them to scratch a bit with everyday wear, I personally think this adds to their charm as they mould to your everyday life (go look at grandmas wedding band, bent and worn from a lifetime of love) Everyday wear is the best way to to stop your jewels from tarnishing, though your natural oils/ph and moisturizers/sunscreens may cause some discolouration.
A hot tip for removing tarnish of gold and silver jewellery is to place some aluminium foil in a bowl shiny side down, then put in your jewellery and completely cover with bi-carbonate soda and then slowly pour over boiling water, leave to sit for an hour then rinse in fresh water.
Ultrasonic cleaners can be a good investment but take heed, not all gemstones are created equal and some are not safe in there. The safest way to clean your jewellery is with warm water, dish soap, a soft toothbrush and a little bit of elbow grease.
if you’re unsure about anything please don’t hesitate to email me at firstname.lastname@example.org