Bronze Casting Techniques

Direct lost-wax casting
Using a difficult technique called the direct lost-wax process, 17th Century Dutch artist Adriaen de Vries made hundreds of bronzes during his lifetime. During the casting process, the wax of the original wax-and-clay model melts out, or is "lost," hence the technique's name. Because the model disappears, each bronze cast produced is a unique original. If the casting fails, the sculptor must begin again. Thus, only the most accomplished and confident sculptors worked in this method.
See also a video on indirect lost-wax casting

Source: Getty Museum website

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