Plus, who doesn't love to share a good mystery?
Maria Goretti would be a viable option given the subject's youth, the presence of lilies and what could be construed as the crown of martyrdom, but again, the fact that the subject is presented in a cave kept bringing me back to St. Philomena (who during her various tortures was kept in a dungeon cavern).
Several ladies pointed out the absence of an anchor or arrows, two symbols of St. Philomena. I agreed that both were missing, but since neither were the actual instruments of her martyrdom (just her torture), the artist could have chosen to represent them, instead, through the colors of the angels' robes.
St. Philomena was tossed into the sea attached to an anchor but was rescued by an angel in full view of the city. The first angel is wearing blue. Next, Diocletian attempted to have her killed with flaming arrows (that turned on the archers in mid-air, killing them). The second angel is in a fiery gold color.
Lilies represent purity and happen to be used for many saints in sacred art. The way her hands are crossed over her heart points to her chastity (because again, chastity is not really about sexual prudishness so much as a state of being where one protects the virtue of one's heart). However, I couldn't account for the three sanctuary lamps other than to assume they represented the Trinity.
So while St. Philomena was the front-runner, no one was fully convinced this was really a picture of her.
A few weeks went by when I came across this image of St. Seraphina:
Apparently the daughter of "The Lord of Roses" in Italy, she went off to live as a hermit in a cave until her saintly death. Her remains were carried around the city 3 times after her death which brought an end to the Plague there (which I suggested could account for the three lights) and while the crown that awaits her isn't that of martyrdom, it can easily be the crown of immortality that artists sometimes used to depict the triumph of saints over sin (with the reward being eternal life in Heaven).
So after reading up on this new saint, the group of us is pretty certain that the portrayed is St. Rosalina. She is now patroness of Palermo, Italy as well as several cities in Venezuela.
Unfortunately, we have no artist name to go off of, no date it was painted, and no other information than that which you see above. That being said, after a month of us all going back and forth, I'm feeling pretty good about our chances at having figured out who our mystery saint is! Besides, even if we're wrong, we've all learned about several new saints in the process.