Not really, solid copper would need a higher temperature. It could be copper dust if there was some work done on the piping recently. It could also be that this is burning on bottled propane, which can contain some sulfur compounds that react with the copper, making the flames green. Or it could be cleaning agents if it’s recently cleaned. (according to some googling around) I also found this youtube video, but it’s kind of shitty, especially that it’s saying it’s due to acidic cleaner, and rinsing with vinegar should help.
Could it be consuming copper from the burner if the O2 mix is off?
Not really, solid copper would need a higher temperature. It could be copper dust if there was some work done on the piping recently. It could also be that this is burning on bottled propane, which can contain some sulfur compounds that react with the copper, making the flames green. Or it could be cleaning agents if it’s recently cleaned. (according to some googling around) I also found this youtube video, but it’s kind of shitty, especially that it’s saying it’s due to acidic cleaner, and rinsing with vinegar should help.