Thank you for your enthusiastic words, Jim
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Indeed this is an unusual example in all its details. But soon as i posted it here, some acquaintance i have, dedicated to these matters, reminded me of a similar, almost equal, example in exhibition in the Portuguese army museum of Lisbon. In fact all details match, since the key clue
VIVA PORTUGAL on the blade, a motto profusely used whilst the restoration of independence from the Spanish Filipes took place (1640-1668). The crown is no doubt that of Dom Joćo IV, who was then acclaimed King of Portugal.
Amazing that the length and profile of both swords is practically the same.
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