And that bust in the photo does bear as strong resemblance to a reliquary. That looks like an oval window in the chest, where one might see the relic, if the lighting were better.
Yes, David. When I zoom in on the gold oval, I can see a crack in the glass (I mean, I didn't realise it was a window until you mentioned it. Zooming in on the image and seeing the crack confirmed that it was a window.) Kathar1na's link gives the whole story (more or less): "On September 14, 1601, ... , he donated to the parish a series of famous relics ... a medal of Saint Torcuato, disciple of Santiago, bishop and martyr, with a relic of his inside his chest, on a golden litter; another medal of San Ramiro, martyr, with a relic of his inside the chest;" I think that the Spanish must have a couple of typos; I think 'medalla' should be 'modelo'. And the 'B' could indeed be for 'Bendito', though I thought that the title 'Blessed' was conferred to a person before sainthood was conferred. Since Ramiro is a saint, I would have thought the inscription should be "SRAMIRO", but that's a minor detail.
Thanks, Canuck, Kathar1na and David.