The Monnaie de Paris produced a series of aluminium pattern piastres in 1931 for French Indochina as the administration explored cheaper alloys — silver had been the standard, but falling colonial revenues and metal costs were making the full-weight piastre increasingly impractical to produce. Most trial pieces from this program were struck in multiple diameters; the discrepancy between this example's 36.94mm and the Lecompte reference diameter of 37mm is consistent with known dimensional variation across surviving specimens rather than a distinct type.
The Monnaie de Paris produced a series of aluminium pattern piastres in 1931 for French Indochina as the administration explored cheaper alloys — silver had been the standard, but falling colonial revenues and metal costs were making the full-weight piastre increasingly impractical to produce. Most trial pieces from this program were struck in multiple diameters; the discrepancy between this example's 36.94mm and the Lecompte reference diameter of 37mm is consistent with known dimensional variation across surviving specimens rather than a distinct type.