Jewellery Cleaning refers to the periodic cleaning required to maintain sparkle and beauty. Pure “Noble” elemental metals (for example, 24 karat gold) do not oxidize or tarnish: however, almost everything else does, and the vast majority of jewellery is formed from alloyed precious metal. Sterling silver and coloured gold are the most common alloys used in fine jewellery, and they need occasional maintenance to ensure that they always look their best.
Gold is more prone to tarnish when it has a higher level of alloy, or is of a lower karatage. Some materials used in alloys can accumulate as a dark coating, also known as a patina, in recessed areas of the piece. Copper in sterling silver is an example of this: it is because of the alloyed copper that sterling silver pieces look orange, brown, and finally purple-black if left to sit without maintenance. Patina is a feature that is often valued and desirable in jewellery, especially estate pieces, as it indicates age and creates character. However, the same discolouring in fine tableware is definitely not a “plus”.
Interestingly, tarnish forms much more rapidly in homes with faulty furnace heat exchangers. The fumes that travel through air vents can promote the process (and also poison the occupants). I know of one elderly couple who came in to complain about the lack of durability of a residual coating in a polish: after I explained the possible cause, they went home and discovered a hole in their furnace unit. The rapid tarnishing served as a canary in a mine, possibly saving these peoples’ lives.
There are some anti-tarnish coatings available, but many of them can become worse than tarnish in the long-term. One product from the 1960’s, called Aris, was a spray-on clear lacquer that became a disaster for customers who didn’t follow the manufacturer’s instructions precisely. When they used an abrasive polish, the coating scratched and fogged, and the more it was polished the worse it looked! The lacquer is no longer available, but modern products sometimes use similar technology.
Jewellery Cleaning and polishing removes tarnish and dirt, but does not affect any scratches or surface wear. If your piece shows signs of age other than tarnish, you can come in to have it refinished. Refinishing goes a step further in the renewal process. The surface of the metal is treated until surface scratches, dents and any other imperfections are removed. The process takes longer than polishing, but it is often the only way to restore damaged pieces to their original condition. Refinishing always includes polishing as a final step.
Plating, or re-plating, is the ultimate process for renewing metals to their original condition. Plating a piece of jewellery can change its colour — for example, from yellow gold to white gold — or brighten the original metal colour. It requires both refinishing and polishing, as the surface of the piece must be perfect for a new layer of metal to bond during the plating process. Since the new layer of metal added during the plating process is usually only microns thick, it will not fill in engravings or delicate detail work. To ensure that your piece’s plating has a long life, we usually give multiple coatings with a polish between each layer. We are only able to perform re-plating jobs on small pieces of jewellery because of strict regulations placed on the use of plating chemicals. Since the re-plating process involves dangerous acids and chemicals like cyanide, facilities for handling large pieces are located far from residential areas and must adhere to strict regulations.
If you own a piece of jewellery that has seen better days, bring it in for a free quote on our renewal services!