These glorious warm summer evenings go hand in hand with the distinctive chink and rattle of a gin and tonic being enjoyed. Gin has certainly become the most popular and fashionable alcoholic drink of late. Aside from a refreshing sundowner, gin is frequently believed to be good for cleaning diamonds – but between you and me, it’s not the best liquid on the house the you could reach for to achieve sparkling jewellery. I often see the result of a disappointed jewellery owner that still has rather dull diamonds despite being soaked in gin for several days (the jewellery not the owner).
The theory behind the gin method of cleaning is interesting. A diamond crystal is configured in a particular way that attracts grease – this is how the rough diamonds are separated from other rocks at the mine. The rough stones are passed over a grease table, the diamonds stick, the others roll on by.
It is believed that alcohol will cut through the grease that covers diamond jewellery, but not without a good scrub to remove stubborn particles and bits of debris that tend to hang around under settings. For home cleaning I find washing up liquid and hot water, with a small tooth brush is much better, similarly, the gin is much more effective served with ice and tonic!
Cleaning is something I am enthusiastically drawn to. One of my favourite ‘experiments’ as a child was to drop the dull brown coins of my pocket money into a saucer of HP sauce, let them soak for a few days and remove them to find beautiful bright glowing treasure, with a shine that was miraculously released for all to see. Sudden the pennines had much more value to me, and the sweets bought with them tasted extra special. It was magical alchemy to my 4 year old eyes – but of course, as my parents well knew, it was a simple kitchen chemistry trick with very satisfying results!
On a professional level, it seems natural to give a piece of jewellery the appearance that was originally intended by the jeweller who made it, and beheld by the first who wore it. There is something deeply satisfying about taking an item that looks tired, dirty and well worn and transforming it to it’s former glory. Antiquities specialists would rightly argue that there are pieces with historical importance that need to be left as untouched as possible. But in general, a good clean and polish is simply good maintenance.
Polishing a piece of jewellery in the workshop usually involves gently removing any large scratches and dents from the metal by using an abrasive paper or sometimes a small abrasive wheel on a pendant motor (akin to a ‘Dremel’). Then a bench motor is used with a series of circular cotton and felt mops, working through grades of wax-based polish to eventually reach a fine and mirror-like shine. The motor is a powerful beast and something to be treated with respect. An extraction system is needed to take away the dust which is filthy. Even so, inevitably, some of the black polish ends up on face, hands and clothing, usually just before having to make a respectable appearance.
For a few years I taught a jewellery-making evening class. My most worrying moments were always when a student stepped up to the polishing motor with something large and beautiful that had taken weeks to create. The final polish of such a piece could easily be the final moment of it’s existence. One incident that stands out most clearly in my mind is the silver toast rack that lasted no more than 10 seconds into the polishing process before disaster struck. It got caught on the edge of the rotating mop. Within a nano-second, it was flung around the spindle and thrown against the workshop walls, reducing it to a ball of crumpled silver wire similar to the raw state it started life as! Thankfully no students, fingers or classroom structures were damaged in the process – teaching a quick-release grip is always an important first instruction.
To remove remains of polishing compound and dirt, the main workshop equipment used is an ultrasonic tank. The steel tank of hot water and detergent uses ultrasound to agitate the dirt from an item. Home versions are available, but are not as powerful. The ultrasonic is extremely effective, but can have surprising and unwanted results with certain stones. Some gemstones are very sensitive to cleaning and a knowledge of them is vital to avoid any mishaps. Tanzanite or opal, for example will disintegrate if dipped in the ultrasonic, and a diamond that has been glass-filled to enhance it may well split in half.
Emeralds are cut and facetted with the addition of oil to cool the stone. Because they have many fine gaps and fissures in the crystal structure, the oil seeps in. This is a good thing aesthetically – it makes the stone look clearer and less cloudy. But clean them in a harsh detergent and the oil leaches out – suddenly your beautiful emerald is looking worse then when you started!
Official chains of office and military silver usually lead busy lives, and I’m quite glad they can’t tell their tales! Occasionally I’ve been involved with cleaning and restoring such pieces and have removed all manner of dirt from them. Mayoral chains seem to be just the right length to dangle into food at the dinner table – I usually have to remove several layers of dried soup from them before any restoration work can begin!
The most notorious precious metal to dull and tarnish is sterling silver. Cleaning will remove a small layer from the surface but some cleaning products are more destructive than others, so gentle is the best option. Over the years, I’ve seen a few ancient church chalices that have been exuberantly polished to the point of collapse.
For home sparkling, the safest method is usually a warm soapy water wash, gentle scrub with a soft toothbrush, rinse and a buff with a gold and silver polishing cloth.
If in doubt, mix a relaxing gin and tonic and seek advice!