Some vintage pieces should not be over polished and looking too brand new, as a subtle vintage patina adds character and value to a piece! So do check with your jeweller before you begin.
For other 14K and 18K gold jewellery that is more contemporary, here are some simple tips that will restore your pieces to their former glory in no time.
Give your jewellery a good bath in soap and water. Add a few drops of dishwashing liquid to a bowl of warm water. Let jewellery soak for 15-20 minutes before blotting off excess moisture with a clean dry cloth. Leave the item on a fresh cloth to air dry before storing in jewellery pouch. Note: This works well for items that are not set with precious stones.
For items that are set with gemstones, best to check with your jeweller before commencing. Many gemstones do not take well to cleaning with water and soap (especially emeralds and pearls). For diamond jewellery, you can dip a clean cloth into the soapy mixture before gently polishing over the gold and gemstones. Then, using a separate cloth that has been dampened with water, carefully clean off the soapy residue. Blot off excess moisture before air-drying and storing. For awkward spots that cannot be reached with polishing, try brushing on the soap mixture using an old soft bristled toothbrush or a pipe cleaner.
For stubborn stains or slight tarnishing to certain alloys, you may also substitute the soap and water combination with one third ammonia to two thirds water.