Resized Platinum Band -Black Mark

[M2]

Hi, i hope someone can help me with this question. First off my wedding band is platinum and the middle portion of the band is brushed. I recently resized my brand new platinum band to a smaller size b/c appartenly they either sized me too large or i lost weight maybge 5lbs at most. I noticed while inspecting my band that there is a tiny black line between the beveled brushed platinum part and the non brushed platinum portion. The black line does not trace around the entire band, is only on one side, and is maybe at most 1mm long. What would cause a black mark on the platinum band as it looks like is a black scratch. he said it was caused by the laser. Is it white gold that they used to solder the two bands together? If so i should i ask for a brand new band or have them redo it without the white gold?


please advise.

thanks,

Mike