To make sure your gold filled jewelry lasts a happy life, avoid chemicals, sweat and wearing them under rough conditions as much as you can. To keep them clean, wipe them off with a soft jewelry cloth after use. If you believe your jewelry was exposed to any chemicals for example body lotions, perfume, etc.. wash and rinse it off with warm water and mild soap. Dry with a soft cloth thoroughly. It is better to remove your jewelry while sleeping as the dainty chains might get caught in bedding or apparel which might cause damage. Gold filled might tarnish by time however it has a much longer life compared to gold plated items.
Sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper which makes it tarnish by time. Try avoiding exposure to chemicals, sweat and rough activities. Sterling silver can easily be cleaned with a soft jewelry polishing cloth.
Argentium is 93.5% silver, 5.5% copper and 1% germanium. When a sterling silver piece tarnishes, it's because the copper in the alloy is reacting to the air and turning colors. As the copper amount in Argentium is less than sterling silver, argentium is less likely to tarnish. You can clean your argentium jewelry with a soft jewelry polishing cloth. Always try to avoid exposure to chemicals, sweat and use during rough activities.
Brass jewelry will tarnish by time even the tarnish resistant ones. That is a natural reaction of the metals to air. The tarnish can be sanded off with an extra fine sanding block and polished with a matte or shiny polishing block depending on the desired finish.
Copper will tarnish by time, it is the natural reaction of the metals to air. The tarnish can be sanded off with an extra fine sanding block and polished with a matte or shiny polishing block depending of the desired finish.