Gucci Boston bag---watermarks leather??

[joyfishyu]

I noticed there are something like water marks on the bottom of the bag. Someone told me that was called "watermarks leather" and it is unique for gucci hard boston bags since fake boston bags can not achieve that look.

Yet I feel doubtful about whether those are stains indeed. They don't appeal to my eyes anyway.

Does any of you ladies have bought that bag at boutiques? Or, has anyone heard about such saying also?

Thanks.

Attached is the style I was talking about:

 

[curtism]

have you tryed to get them off ?

 

[joyfishyu]

I feel it will be better to know what they are first before any action