10c violet 'Momotombo' TRAIN postal stationery envelope with '1908' handstamp in deep violet (H&G B70) used with oval LEON cancel dated SEP 14 1908 with two strikes of circular 'OFICINA DE TRANSITO' marking in purple on front. Addressed to COSTA RICA with SAN JOSE arrival cds on front. Part of backflap missing but otherwise fine & scarce. The only recorded example of the envelope going to Costa Rica.