Thanks for the translation — in other words, the Rosary.
The Divine Mercy chaplet beads...which, oh, by the way, happen to be the Rosary, but, well...(religious goods stores make money from selling both Rosaries and Divine Mercy chaplets)
miseri = “miserable, wretched.”
cor (pl. corda, although cordia is possible) = “hearts”
The only instance of misericordina at vatican.va is this link:
Possibly the n was introduced in Italian, although I think it is a misspelling.