Types of Silver Clay explained –
Precious Metal Clay and Art Clay
Metal clay is a suspension of tiny particles of metal in a clay binder,
which can be used to make jewellery, beads and small findings. The
beauty of metal clay is that it can be manipulated in the same way as
any modelling clay, but once fired the binding agents are burnt off
leaving the metal form intact. Although there is a certain amount of
shrinkage (between 10-15% for the more modern versions), very fine
detail can be achieved, including impressions that would require casting
in any other method of metalwork.
Silver metal clay results in objects containing almost pure silver (also
known as fine silver) which is ideal for enamelling. There are two
popular brands available – Precious Metal Clay (also known as PMC)
and Art Clay Silver (ACS). Precious Metal Clay was developed in the
early 1990’s in Japan and consists of microscopic particles of pure
silver (or fine gold powder) and a water-soluble binder which burns off
during firing. The original formula of PMC (now called ‘Standard’) has
to be fired in a kiln at a temperature of 1650F and has a high shrinkage
rate of around 30%. Two additional versions were later developed called
PMC+, which can be fired at 1490F and PMC3, which can be fired at
temperatures as low as 1100F. Both of these later versions of PMC have
much lower shrinkage rates, allowing much finer detail to be worked into
designs.
Art Clay Silver (ACS) was also developed in Japan and is similar in
consistency to PMC+. The main difference with ACS is that it can be
fired using a hand-held torch or gas oven. Because of subtle differences
in the binder components and the longer firing times, ACS benefited from
having a considerably lower shrinkage percentage – only 8-10%. This
means that ACS can be worked in more detail without any loss of
definition in fine work. Art Clay Slow Dry was introduced soon after,
which has a much longer working time before requiring firing, allowing
intricate work to be moulded into the clay with no loss of malleability.
Art Clay 650 and Art Clay 650 Slow Dry are now becoming increasingly
popular, as not only do they have a longer working time but can be fired
at temperatures as low as 650C/1200F. This allows jewellers to
incorporate glass and Sterling Silver into the designs without fear of
damaging the components. AIDA, the manufacturers of ACS have also
introduced Oil Paste, a product only used on fired metal clay or milled
fine silver, and Overlay Paste which is designed for drawing designs
onto glass and porcelain. These two products have allowed the use of
metal clay products to be incorporated into a whole new range of designs
and mediums, expanding the potential of this product.
Metal clays allow jewellers to work with a material that is as malleable
as ordinary modelling clay but produces fine (almost pure) silver
jewellery of exquisite intricacy and beauty. Once polished it has a
lustre and shine that is easily comparable to cast silver and because of
the development of the products over the last few years shrinkage is now
no longer an issue. The type used depends on personal preference as both
types have their advantages, but incorporating metal clays into your
jewellery design gives you a new medium to explore with beautiful
results.
Article Source:
http://www.ArticleStreet.com/
About the Author
Adam Hunter – E-commerce Marketing Manager of
cooksongold.com. Cookson Precious Metals offer a choice of
jewellery making supplies from
over 10,000 products including gold and silver findings, tools,
silver art
clay and gold and silver sheet - gold, silver, platinum and
palladium plus technical information for jewellers, jobbers, designer,
craftsmen, artisans and students. Contacts Adam Hunter E-commerce
Marketing Manager Tel(DDI): +44 (0) 121 212 6491 E-mail:
adam.hunter@cooksongold.com
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