Mappin and Webb punch bowl

This punch bowl has come to me from my Grandparents. I love it! It’s very large and heavy. The hallmarks are a bit rubbed due probably to my Grandmother’s assiduous cleaning, but still legible. I think it probably exceeds the value at which items must be named on my insurance (NZ$1000 - about pounds 350).
I think it’s 1937, but the pattern looks earlier. It has three handles equally spaced rather than the more usual two. I wonder if in fact it’s soething other than a punchbowl? My grandmother used it for trifle at Christmas!
It weighs 2 ilbs 11 1/2 oz (on my kitchen scales), is 250mm diameter and stands 160mm high.
Any info and a value would be gratefully received! Thanks
hallmarks.JPG
punch bowl base.JPG
punchbowl side.JPG

looks like a punch bowl. 1937 is right.

It should be insured for around £1200

Regards // Jonathan

Thank you, Jonathan, much appreciated
-Rowena