I don't believe so ,never seen marble either .
Superior is definitely an old school traditional "Italian" bakery- the fresh bread, calzoni, rolls are Excellent! Cranston still has a large Italian community, many bakery's as well- best bet may be Whole Foods or market bake shops for fresh Artisan breads like marble ryes & pumpernickel.
We do carry it but usually you just need to ask 😀
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