Investment casting in the context of "Refractory"

Lost-wax casting – also called investment casting, precision casting, or cire perdue (French: [siʁ pɛʁdy]; borrowed from French) – is the process by which a duplicate sculpture (often a metal, such as silver, gold, brass, or bronze) is cast from an original sculpture. Intricate works can be achieved by this method.

The oldest known examples of this technique are approximately 6,500 years old (4550–4450 BC) and attributed to gold artefacts found at Bulgaria's Varna Necropolis. A copper amulet from Mehrgarh, Indus Valley civilization, in present-day Pakistan, is dated to circa 4,000 BC. Cast copper objects, found in the Nahal Mishmar hoard in southern Israel, which belong to the Chalcolithic period (4500–3500 BC), are estimated, from carbon-14 dating, to date to circa 3500 BC. Other examples from somewhat later periods are from Mesopotamia in the third millennium BC. Lost-wax casting was widespread in Europe until the 18th century, when a piece-moulding process came to predominate.