Spot On Black Molly. Help Please!

[Poysin]

Ok, so I finally joined up to see if I could get and awnser that seemed to be focused on what I am worrying about. I recently got three black mollies, and a ghost shrimp. My black mollies have all been very fine, as well as the shrimp. They haven't changed at all. But one black molly came with a spot of white on it, no one at the pet store seemed to notice so I brushed it off.But It's a fairly large white circle just behind her eye. She dosn't seem bothered by it, active, swimming around lots. She eats the same as the rest. But I'm not sure If i should be worried about her or not. I couldn't find any information regarding my situation. Any and all responses are greatly appreciated. I love them and don't want them to be sick becuase I am clueless.
 
(Ive attached a photo so identifying it would be easier)
 

 
Thanks!
 
 

 

[Manniac]

Hmm that's definitely odd... I've never seen anything like that...
 
Can you maybe tell us what the texture of it is like? It's kinda hard to see clearly in the picture. Is it fuzzy or lumpy or smooth or does it look like her other scales, etc...