Other mistake: In the scene where we see Professor Bruttenholm talking to Myers about Abe's origins, we see the professor pick up what he specifically describes as "rotten eggs" from an open bowl and place them into a tube. The eggs have been sitting out in the open the whole time, but Myers only reacts to the smell once Broom picks them up.
Other mistake: All the time that Abe has been underwater reading multiple books at a time, he's never designed a machine to turn the pages? Even a pointer on a long arm would work serviceably. (00:19:50)
Other mistake: Every time someone gets skewered through with a blade in this film there's never any blood on the blade afterwards. (00:41:50)
Other mistake: During Hellboy's second fight with Sammael, they crash through the ceiling of a subway station, causing panic. While most of the extras are scattering in terror like normal people would, in at least two different shots, you can see a female extra with dark hair who not only looks completely disinterested, but is moving at a slow, leisurely pace, staring down at the ground as though this is commonplace. In fact, it almost looks like she's smirking in one shot. Possibly the world's worst extra.
Other mistake: When the camera pulls up from Hellboy embracing the dead Professor Broom, you can see that several of the evidence numbers are present more than once. Evidence numbers exist to identify and correlate different pieces of evidence without doubt in photographs of the crime scene. It would just be nonsensical to re-use them on different pieces of evidence on one and the same crime scene.
Other mistake: At the train tracks, before Abe enters the water, he turns his blue locator off, but, later, one of the agents blue lights goes on and he says "Hey, it's Abe." But Abe doesn't turn his locator on until he leaves the water, injured and in need of help.
Chosen answer: Her jewelry does not melt either because the fire wraps around her and shoots outward enveloping her and her clothes and jewelry in a safe environment that allows her to breathe without burning the air going into her lungs. Plus if it burned her clothes it would get an R rating.