Stripes on Firescale Free Silver

Metallurgical Help:Stripes on Firescale Free Silver

Hi All I recently purchased a piece of firescale free silver. It had
darker grey stripes over one side which I thought would disappear
with rolling, sanding etc.With sanding indeed the stripes seemed to
disappear but reappeared when the work was annealed. In fact along
one edgelines appeared similar to the lamination lines when you roll
out mokume gane. I returned the metal for inspection and was told
that there was nothing wrong with the metal and that these were
lines from the rollers, and when polished there was nothing to be

This does not make sense to me. If this was the case, then surely if
I rolled in another direction they would disappear? Also you would
not expect them to keep on reappearing. To suggest that with
polishing you can’t see anything is a cop out because the reflection
makes it difficult to see any flaws in the metal and one wonders if
this will be visible with a mattflat surface over time.

Anyone have thoughts on what this could be?

Christel van der Laan