Was This A North Providence Miracle?

Do you believe in miracles? A few days ago, traffic was backed up for a mile as drivers slowed down in front of the Church of the Presentation of the Blessed Virgin Mary in North Providence to catch a glimpse of what some are saying is the miraculous appearance of the Virgin Mary holding baby Jesus. The image appeared as rain poured off the grey copper cross atop the church's steeple and didn't fade or dry up after the rain passed. Hundreds of people, by the hour, said it was something divine. Perhaps not as defined a message as they'd like, but a sign from heaven, nonetheless.

However, metal experts are saying that tarnish forms on copper from oxidation, so the discoloration that looks like a divine form is most likely an earthly chemical reaction. What do you think?

[WPRI]