Black spots on baby noses?

I am hoping for any information about something strange that's going on! My most recent litter has 4 babies, 5 days old, all of which have developed a blackish discoloration across the nose. They seem healthy and regular otherwise. What is this, and what is causing it? Is it cause for concern?

Pics?

I happen to be brilliant and lost my camera. It's somewhere, I just know it.

Could be some kind of mold? Does it brush off with a Q-tip damp with warm water? Would warm soapy water be OK? The soap could kill spores.

Or could it be pigment? How strong a magnifying lens do you have? Check it out!

OH, it isn't pigment, but I've been told it's normal. It appears to just literally be dirt or poop or something. It's a little bit crispy.

Try the swab. See if it comes off

Weird...... lol

could be dirt or dust from the bedding maybe??

Well the problem has gone away, but not before I got my answer! These babies were GRIMY!!! They were filmy and dirty, lol. Now they are fully furred and fat, extremely healthy, and clean. So strange!!!

You must speak to their mother about that!