Casting metal is one of the oldest known techniques of jewellery making in the world. Perhaps since man discovered fire we have been trying to burn and melt different materials. Making shapes from molten metal naturally progressed from this.
Once we understand casting it is quite an easy technique to repeat over and over again. As long as we follow the same principles we almost never have mishaps. Even if we do make mistakes with our cast silver it doesn't matter anyway as we can just melt it down and try again. The only waste we create is either some burnt delft clay, gas we have used or wax if we are doing the lost wax method.
My preferred method of casting is using delft clay. It is a type of sand with added oil. It allows the sand to be molded, hollowed and re-used. For this type of casting we require something to make indentations in the delft clay. Many people carve wax. Not candle wax but a special jewellers wax. It is a harder substance and easier to make intricate shapes. I prefer to use perspex. It is almost impossible to damage and destroy which means a carving I make now is still in perfect condition 20 years from now.
For the cast we use casting rings. Two aluminium rings that slot together. We pack the base ring with delft clay, push our carved item into it and then place the top ring and pack more delft clay in. Once taken apart we have an imprint of our carved item. Now we just add air vents, a pouring funnel and we are ready to pour in our molten silver.
A quick tidying up of the final cast obect, filing, cutting off the sprue and then a polish and we have a perfect silver copy of our carved item ready to sell.
For a more thorough step by step guide go to my photo journal how to cast sterling silver jewellery
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