Yeah it no longer melts soft metals. So it's a instant flame that can kill a herd of elk, ignite flammable objects but not melt metal? Though I'm not even sure about that, if a 5hp amulet is in the area of effect is it just immune does it have resistance and still is destroyed? If metal objects get destroyed by the raw damage how is that described melt, crack?
As I don't have all the variables and even if I did I wouldn't have the science background to give the for realz answer I'm happy sticking with fun game play answer. Which for me generally means unless it adds something like interesting terrain change to the encounter I'll ignore it unless the player was specifically going for this effect like targeting a ice bridge the enemy is crossing or about to cross. And I'm willing to have it melt quite a bit of ice if it helps the game. I try to be consistent but how thick/cold the ice is can vary wildly so the effect can as well.
As I don't have all the variables and even if I did I wouldn't have the science background to give the for realz answer I'm happy sticking with fun game play answer. Which for me generally means unless it adds something like interesting terrain change to the encounter I'll ignore it unless the player was specifically going for this effect like targeting a ice bridge the enemy is crossing or about to cross. And I'm willing to have it melt quite a bit of ice if it helps the game. I try to be consistent but how thick/cold the ice is can vary wildly so the effect can as well.