A bronze statue is usually cast in multiple copies. Up to and including an edition of twelve copies, one speaks of an 'original work of art', while an edition that is larger is referred to as 'multiples'.
When a sculptor creates a work, he does so, for example, in wood, clay or plaster. Multiple casts can then be made using the lost wax technique. The first eight casts are considered original. In addition to those eight, with numbers 1 to 8, you can have four extra, the so-called 'épreuves d'artiste' or 'artist proof's'. These are the property of the artist and are in principle not intended to be traded commercially and have Roman numerals: EA I-IV. No bronze statue is 100% identical because casting is also a traditional, manual process. There can sometimes be years between the first casting and the last trenching. And the numbering does not have to be chronological because, for example, a client only wants to buy copies 2/8
Mass production is often accompanied by reduced quality. To curb unbridled reproduction and protect their work, artists made agreements with their foundries to make limited series from the end of the 19th century. In 1966, this was incorporated into a law that stipulated that there could only be eight reproductions and four épreuves d'artistes. This is the rule to this day, while there are actually no legal texts regarding the (re)production of bronzes. Most countries, including Belgium and the Netherlands, base their decision on case law in France, the country with the greatest tradition in this area. And furthermore, they fall back on copyright law, which protects reproduction rights for 70 years after the death of the artist.” Additional casts are often stamped with 'heritage'.
It remains the artist who decides how many pieces can be cast. This can be a unique piece – as Octave Landuyt or Berlinde De Bruyckere do – or there can be fifty if it concerns, for example, a promotional gift or an award statue.
Nevertheless, we see that the majority of the works are cast in 8 + 4 copies; and the artist is not always present because he/she leaves this to the bronze founders. Furthermore, the edition will usually shrink as the artworks become larger. Someone who makes a work of art of approximately 5 to 7 meters must be very successful to produce eight, let alone twelve, copies. As long as the original model exists, new bronzes can in theory be made unlimitedly. However, the wear occurs in the mold: such a silicone mold - in which the wax copy is made - can easily handle twelve copies, but starts to lose quality the further it is used. However, this does not necessarily have to be the case in the end result. Because it is up to the foundry employees to ensure that this loss of quality is eliminated during the various subsequent stages.
How can one distinguish original from copy? If a new mold is made from the final image, we call it a 'surmoulage'. Bronze shrinks when solidifying and is therefore always smaller than the model. So the end product is often smaller.
In addition, certain details are often lost if they are not carefully 'chiselled'. The molds are often destroyed after 12 casts to guarantee uniqueness for the future. But this is also ultimately up to the artist.
Bronze casting is done at very high temperatures. After the mold has been knocked loose from the cast statue, the seams are removed, the casting holes are closed and the finishing process begins, including polishing. The work of the bronze caster is at least as labor intensive as making the statue.