Jewelry is made to be delicate and cared for as such, I use either sterling silver, Argentium silver (higher silver content than sterling, also containing geranium making it highly tarnish resistant! Argentium is also nickel free!) or 14k gold-fill in all of my pieces.
Tarnish is a chemical reaction caused by environmental factors such as certain chemicals, water-whether tap or salt, body lotions and sprays (especially tanning oil), natural body oils, sweat and even oxygen. The best way to prevent tarnish is to keep your jewelry in an air tight container, or a tarnish free pouch. Also avoiding some of the above factors mentioned, and using a polishing cloth to gently wipe away any tarnish when it begins before it piles up too much.
Jewelry can break if not cared for properly, and sometimes due to an error in my craftsmanship. In the event I deem an issue due to my error, I will gladly repair for you at no cost. Otherwise I will charge a small fee for repairs plus shipping costs. To inquire about a repair please contact me at firstname.lastname@example.org