Is This Mold or Rust? Something else?

[rksegal1]

What is this? I discovered it in a heating vent within my home on drywall, not metal. I also noticed some areas around nail heads that have a similar coloration, but there isn't as much of it. I've only ever seen this kind of thing outside on rocks and wood. It seems to be a permanent fixture on the drywall and isn't powdery at all. I haven't attempted removal as I have no idea what it is.

Please see the photobucket pic for an image:

http://i34.photobucket.com/albums/d120/ ... usi8zs.jpg

[Les]

Rebecca,

the photo is not very good. can you post another as an attachment?

[kurt]

Take an establishing shot, i.e., pull back and show us what we're looking at, then give us a close up.

Is there any amount of dampness or moisture that collects in any of the locations where you see the red stuff? It looks like there might be a little blackish staining on the wood next to the duct, which usually means some amount of moisture.

I sometimes see a strange reddish moldy crap on shower curtains. There are molds with a reddish tinge, but they aren't going to grow without moisture.

[rksegal1]

Hey guys.

I've tried getting a better picture of the stuff inside the duct, but it's not working out too well. The idea of taking an establishing shot is a great one, so I snapped two: one with the vent cover on and one with the vent cover off.

Upon closer inspection, it almost looks like whatever it is is seeping through the drywall. Not sure if it's a strange chemical reaction to something or what. I took a second picture with a flash, and I see little black bits. But when I look with my naked eye, in the actual heating vent, there's no black. Not sure what this means as I'm no camera expert! Sorry for the quality of the photos. This is the best I can do

http://i.imgur.com/Nn506E3.jpg

http://i.imgur.com/Nn506E3.jpg

http://i.imgur.com/mBbdakN.jpg

[kurt]

I'm stumped. No idea.

[inspector57]

Just a WAG but it looks like the red is the underlying color with paint/texture splatter over it to me.

[Jim Katen]

Just a WAG but it looks like the red is the underlying color with paint/texture splatter over it to me.

Exactly. It looks like a previous layer of red paint.

[Marc]

Or rust coming through thin paint.

Marc