10 centimes Epreuve en aluminium de Dubois

Henri Dubois served as chief engraver at the Paris Mint from 1897 to 1930, and these aluminium épreuves were struck not for circulation but as presentation pieces submitted during the competitive trial process that preceded the adoption of new coinage types. France's decimal system was well established by this point, but the Third Republic periodically reopened design competitions to refresh minor denominations — the 10 centimes being a perennial candidate given its heavy daily use and consequent rapid wear in bronze.

Aluminium was the standard trial medium at Paris precisely because its low density made unauthorized melting economically pointless. The GEM references cite at least five distinct varieties across this four-year window, suggesting multiple submission rounds.