Postal stationery Edifil 69 with rare mark "COMANDANTE BUQUE PRISIÓN / MAHÓN / DE / MAHÓN" very well stamped. Tarragona postmark dated on Februery 16, 1937, and text on the back of the same date.
The sender is Hermenegildo Ciurana, priest of Albarca (Tarragona), detainee in the prison ship, who survived the war.
In Tarragona harbor there were prison ships Cabo Cullera and Río Segre, renamed Cabo San Sebastián. The prisoners in Cabo Cullera were moved to Río Segre, and after october 1936 they were transferred to Mahón steamship, as the other ships were in wreckage. On late 1936 another ship, named Isla de Menorca, was transformed in a floating prison also, as the Mahón was overcrowded (see Arxiu del Port de Tarragona, "El documento del mes", núm. 27, Feb. 2014).
In the Spanish National Library there are fiver postal stationery with this same mark and from the same sender.
On the back's bottom right corner, guarantee mark of British expert Ronald G. Shelley.