Silver clay

Silver clay is the generic term used for pure fine silver powder, mixed to a plastic mass with water and a filler (cornflower is frequently mentioned as a filler).  The original product was the result of a patented process by Mitsubishi Industries, to make use of reclaimed silver from silver-gelatine photography products.  This plastic mass can be shaped and formed in much the same way as salt dough, then allowed to dry.  Finally it is sintered by heating to around a dull red heat for some time, to produce an intriguing miniature version (because of the shrinkage involved) of the original shape.   The pictures below illustrate some of my tinkerings with this material. The left-most picture shows a round block of plaster into which I carved a couple of simple designs, and above the block are two plasticine pressings (red-brown colour). The centre column of the same picture shows two silicone rubber moulds made from these pressings (so I could get the depth component of the  image the way round I wanted it), and finally the right column of the picture shows the (fired and polished) silver clay items. The centre picture gives some more shots of the fired silver clay, together with some spiky shapes (designed to have cells for enamel) made by the same process, this time making the silicone rubber mould directly from some pieces of mesh. The large silver leaf was originally moulded with silicone rubber, but it gave a much more interesting and useful cast after making a secondary silicone rubber mould from the original rubber mould (to invert the depth dimension); the fired silver clay cast is illustrated. The pair of eyes only illustrate that more care and talent will be needed to carve the originals. Finally, the right-most picture shows more fired silver clay, together with one example with enamel. My early experiences with silver clay led me to believe it had very limited application, but I now feel that provided it is fired  at a high-enough temperature (say, 800C) for a couple of hours, it sinters well enough to be strong enough for jewellery applications. The manufacturers of the various species of silver clay take pains to emphasise that it can be fired for a short amount of time (10 minutes in one case), and to my mind thus do the product a disservice, since it then ends up disappointingly weak.