On one of the star facets and the top of one of the kite facets there is a grain line, below this inside the diamond I can see reflective internal graining. This is looking with a loupe and is confined to part of the star facet. Is this anything to worry about?
Internal grain orientation, may be something you want to take up with an independent appraiser. I do not know if this would pose any real problems, but its something to
consider while making a purchase.