Non-tarnish or tarnish-proof means it does not tarnish ever, while tarnish-resistant means you can keep your jewelry looking its best through proper care and doesn't tarnish just after few uses. Only real solid gold doesn't tarnish.Our pieces are 18K Gold Plated Sterling Silver, with an extra layer of tarnish resistance called e-coating to extend the life span of the jewelry. It has the same material as Gold Vermeil, for a fraction of the price.These are best for you if you don't want to spend much on real solid gold, but want to accessorize or switch up your style without having to worry about breaking the bank or irritating your sensitive skin.