30. Recuit(s) Copper hardens very quickly when it is worked in any way (‘work hardening’) and becomes very brittle. Thus it has to be softened by heating and slow cooling ( recuit ) - annealing - before it can be worked again. If this were not done the punch would not stamp an impression of the letter, the copper would fracture. The verb recuire is used because, in common practice, tempering - of steel for example - by heating to high temperature and cooling very rapidly - usually by immersion in water – (‘ rougir et tremper’ ) which hardens the metal, is usually followed by controlled softening - annealing - for which the metal is re -heated - ‘re-cuit’ - then allowed to cool slowly. Hence , recuire came to mean the process of annealing.