The best way to clean gold jewellery is to soak it in a concoction of warm water and non-detergent based soap. How long you soak it depends on how much debris the piece has accumulated. Anything between a few minutes to an hour or two is acceptable. Once you remove it from water, rub it gently with a soft cloth.
For intricately designed gold pieces with dirt particles stuck in its crevices, use a soft bristled, preferably worn out brush and gently rub till clean.
Silver jewellery is most susceptible to becoming tarnished over a period of time. If you do not want to get it professionally polished, a good way to clean it at home is by taking a dish bowl and placing a piece of aluminium foil at the bottom with its dull side facing down. Fill another bowl with water and bring it to a boil. Put 1 tbsp of baking soda per cup of water in the boiling water. Now place your silver piece in the bowl lined with aluminium foil making sure it is touching the foil.
Pour the water boiled with baking soda in this bowl and let the piece soak in the solution for about 10 minutes. Again, depending on the level of tarnish, soak it for longer. Gently wipe it once taken out of water and see it shine!
Plated jewellery is generally made of silver with an extremely thin layer of gold on it. Unlike jewellery made of solid gold, this thin layer of gold plating needs extra protection against scratching and harsh chemicals. The best thing would be to rub it gently with a very soft cloth to get rid of any superficial dirt. However, if it requires a more thorough cleansing then wash it with warm water and mild soap and gently rub with a soft tooth brush. If you rub too vigorously then there is a chance that the gold plating might come off.
Much like gold and gold plated jewellery, diamond jewellery must also be cleaned regularly with warm water and a mild soap to retain its sparkle. Gentle rubbing with a soft toothbrush will help dislodge any dirt in its crevices. Diamonds have very fragile settings because of which any cleaning procedure should be undertaken with a light hand lest the tiny prongs holding the diamond in place become lose or get damaged.
Prevent your jewellery from coming in contact with any caustic chemicals, perfumes, lotions, hair sprays, etc. For this reason, it is advisable to wear your jewellery last and take it off first when you dress up or wind down. Store your jewellery in pouches or boxes such that the pieces do not rub against each other.
Regardless of the kind of jewellery, a little care can go a long way in keeping your jewellery looking new, beautiful and flaunt worthy!