This is an XVIII century cavalry sword with guard of the type known as “boca de caballo” (horse mouth). It’s displayed at the “Museo Arqueológico e Histórico Castillo de San Antón” (archaeologycal and historical museum castle of San Antón) at A Coruña, Spain. I worked there for a few months and this piece was in such a bad condition that I asked permission to treat it. I had to dismantle it and clean each part separatedly. The worst part was the wooden handle, that had cracked due to the corrosion products of the metal beneath.
It was a lot of work but the kind I enjoy, partly because I love swords.