Total Score: 3.02 from 1783 votes (All Votes 5384)
ANTIQUE SILVER WITHOUT WAITING A HUNDRED YEARS!
So, you’ve learnt the basics in metal clay jewellery, and now you want to try something new? Have you ever wondered how they get that nice antique, darkened effect on silver? The answer is Liver of Sulphur (LOS).
LOS is used to give your silver an antique look, a patina, which can be black or a range of colours. The silver reacts chemically to the sulphur, which makes it go darker and darker, until it finally goes black. This is the same process as when silver tarnishes, we’re just speeding it up.
LOS is excellent to use on a textured surface, as it emphasises the difference between the raised and lower parts of the texture. It’s a very satisfying process, dipping and rinsing your pieces, seeing the colours appear. Once you start experimenting you might actually discover that a lot of designs are enhanced by the patina. LOS won’t affect brass or gold decorations. The contrast of the dark oxidised silver against the bright gold or brass is stunning. It can be used on copper, fine silver, and sterling silver, and is ideal for metal clay.
Liver of Sulphur
LOS deteriorates when in contact with air and light. Store it in the dark, and keep the top on. Even when you do this, it will have a limited shelf-life. The solution gets weaker with age – it gets slower and less effective. Using hotter water and a longer soak time can extend the life a little.
LOS has a strong smell. The sulphur in it smells like rotten eggs. As with all chemicals, be sensible and don’t breathe it in. Use in a ventilated area; especially if you are pregnant or asthmatic.
In the UK, LOS is Potassium Polysulphide: a slightly corrosive product, so you don’t want to get it on your skin. It’s mostly sold as rough chunks, from which you break off pea-sized bits. However, the LOS bought from most Art Clay distributors is a mild solution, which is harmless if you get it on your skin. In Japan this solution is actually used in the bath, supposedly healing all sorts of ailments.
The instructions in this article are written for this product. Wherever you buy LOS, make sure you read the data sheet carefully and follow the safety precautions.
Your silver should be finished (brushed, burnished or polished), and clean before applying the LOS. Mix a teaspoon of bicarbonate of soda with a few drops of water into a paste and clean your piece with this. Rinse carefully with warm water. Wear rubber gloves, or you might end up with a lingering smell of rotten eggs on your hands for the rest of the day. You can also use stainless steel, plastic, or wooden tweezers (chopsticks are perfect, if you know how to use them!). Mix the solution in a stainless steel, ceramic, or glass bowl, which you can then set aside for LOS in the future.
For a black patina
For a faster result, heat your silver (with hot water or a hair dryer) before dipping it. Mix a little less than a teaspoon of LOS in a mug of hot (not boiling) water. Drop your silver into the mix and swirl it around. If your LOS is fresh, your piece should go black in a matter of seconds. If your mix is old, or has weakened, it will take longer. Rinse well with hot water. Remember that the darker it gets, the harder it is to polish it off.
For a range of colours
You can also get a beautiful range of colours: gold, copper, purple, blue, blue-grey, and then black. Use the same amount (or a little less) of LOS, but mix it with cooler water, and don’t heat your silver. This will slow down the process and will allow you to stop it at the colour you like. Dip and remove it quickly, rinse in cold water, and repeat until you get to the colour you are after. Experiment with the temperature, heating and cooling your piece, before and in between applying the LOS, amount of LOS, or maybe by adding a drop of ammonia or some salt, which can give you more vibrant colours.
Applying with a brush
You can also apply the mix with a brush. Try painting just parts of the piece for interesting effects. Try layering the LOS, by applying it several times. For a random effect, or varying colours, let it splash or drip from the brush.
Masking effects
You can mask parts of the silver before applying the LOS. This works best on a highly burnished piece, as this is less porous. People use a range of different resists: wax, watercolour masking fluid, or even clear nail varnish (which is removed with acetone).
After dipping
After applying the LOS, polish your piece with a soft cloth and metal polish, to remove the patina on the raised parts and bring out the silver highlights. Don’t use metal polish if you want to keep a range of colours.
I don’t like it!
If you’re not happy with the effect, you can remove the patina by heating your piece with a torch, gas stove, or kiln (be careful you don’t melt your piece if using a torch!). Then you can start all over again if you want to.
LOS will wear off with time, and can also change colour slightly. To protect the patina some people coat it with a clear spray varnish, or a mixture of equal parts naphtha (Bensolene or Zippo lighter fluid) and beeswax. Mix into a cream, apply a thin layer, let dry and then buff with a dry cloth. Remember that varnish can chip off, and can also go yellow with time, but can be reapplied.
Petra Wennberg,
www.SilverClay.co.uk
September 2005
|
  |
