Keep your Jewellery covered when not being worn to reduce tarnishing

Jewellery tarnishes as a result of exposure to the oxygen in air. This process is called oxidation.

Oxidation can be used decoratively in Jewellery that you see as blackened areas but will also occur naturally over time. You can minimize this natural chemical reaction by keeping your Jewellery in a box that absorbs moisture and reduces oxygen.

Small sealed plastic bags are also an effective way to protect your Jewellery from exposure to oxygen. 

Anit-tarnish covers and/or cloths are also available to put around Jewellery or to use in Jewellery roll-up cases to protect pieces from oxygen.

Oxidation will still occur over time, but these methods will reduce the speed with which it happens.

The climate you live in will also affect the rate at which natural oxidation occurs. Warm humid environments will cause Jewellery to tarnish faster than dry environments.

Dry environments can cause their own problems by removing moisture in some gemstones and cause them to crack. An artificially dry environment such as a plastic bag may appear to be the solution for humid environments but will hurt some gemstones like pearls and opals that need moisture to preserve their lustrous qualities.

If you are wondering why some of your Jewellery appears to tarnish more or at a faster rate than other pieces, it can be because some metals and their alloy components react to oxygen differently.

Costume Jewellery – Likely will tarnish but depends on the alloys. Copper based alloys tarnish.

Fine Silver – does not tarnish.

Sterling Silver – Tarnishes as the copper in the alloy reacts to the oxygen in the air.

Yellow Gold – Lower karats will tarnish more as they have a greater copper content than higher karat gold.

Nickel white gold – Tarnishes a slightly yellow colour over time, lower karats tarnish faster than higher karats.

Palladium white gold – Does not tarnish.

Platinum – Does not tarnish.

Some white metal Jewellery (sterling silver, nickel white gold) is plated with Rhodium. Rhodium is from the platinum group. There are six types of platinum that make up this group of metal; they are not alloys but metals with similar properties. Rhodium is hypo allergenic and does not tarnish.

Some yellow metal Jewellery (brass, gold) is plated with high kart yellow gold for a bright yellow finish and because of the higher kart the less it tarnishes.

Just because a metal does not tarnish it can still get dirty. There are chemicals and dust in the air we breathe and this settles on Jewellery forming a fine layer that can resemble tarnish but is not the result of oxidation.

’20 Tips on maintaining our Jewellery’, Gillian E. Batcher, 2013