What is Bronze Resin?
This is a process of casting a sculpture originating as a clay or wax original, from which a fibre glass mould is made & then used to cast the piece in a polyester resin mixed with a thin outer skin of bronze powder. When this is set the outer skin is rubbed down with a wire brush to fully expose the bronze layer . Then further chemicals can be applied to colour the bronze or give it an effect of ageing before wax is applied and polished to the desired level of finish. This final patination can give the work the look of a classic bronze that has aged with maturity or turned green with verdigris weathering
What is Marble Resin?
Originating in the same way as bronze resin, the completed mould is then filled with polyester resin mixed with powdered marble & white pigment. The resultant sculpture is a good representation of a piece carved in real marble or can be used where white is an effective colour for the finished work.
What is meant by foundry bronze?
This is the ultimate material for producing lasting sculptures & has been used for many centuries since the ancient Greeks. Whereas Bronze Resin is commonly called cold cast bronze, the term foundry bronze is used for casting in real bronze ingots in a furnace at up to 1,200 degrees centigrade. The mould produced for a bronze resin cast can also be used to make a wax suitable for bronze casting using the lost wax process. A heat proof ceramic mould is created from this wax original & fired in the bronze furnace where the wax is burned out as the bronze is poured into the mould. When cooled the ceramic mould is broken off to reveal the bronze cast, which then requires many hours of skilled labour, known as fettling, to clean up the surface ready for patination. The chemicals required for the final finished patina are very complex & applied with heat by blow torch or in a second furnace firing. The finishes applied in this way are vastly superior to anything achievable on bronze resin & are almost infinitely variable. After a final application of hot wax the piece will be finished to a standard that will last hundreds of years out of doors.
John has issued bronze editions of many of his sculptures, which typically cost two or three times more than bronze resin versions. This is not so much the cost of the material, but arises from the amount of highly skilled labour required to produce a bronze work & the fact that a new ceramic mould has to be created from the wax original for each one.
Why are the works sold in editions?
If each sculpture is to have a value, it is important to control the number of repeated castings being sold. If the artist is to recover the cost of his original creation he needs to limit the number of sculptures coming onto the market by declaring an edition when it first goes on sale. The size of an edition is usually set at around 25 to ensure each piece has a scarcity value at the price sold. Factory produced sculptures are often sold at places like John Lewis, but as these have unlimited availability they have no more value than as ornaments. Limited editions of sculpture normally have their edition number engraved on the bottom along with the artist’s initials & a date. In addition John usually issues a Certificate of Authenticity with each sculpture showing its edition number & a photograph above the artist’s signature on the document.