I would polish it--the appearance of the oxidation makes me think this is likely low-quality silver and it would be significantly improved with a polish. It's just not very nice-looking patina, and if it were still in its original culture, the owner would keep it clean and polished.
I do not, however, advocate for a blanket policy of polishing the silver on all my dha/daab, etc. Those with very high-quality silver often develop a gorgeous, lustrous patina that is almost blue. I keep those as-is.
