There was a post concerning this mark earlier this year, suggesting attribution to Hamilton:
viewtopic.php?f=2&t=22728No further input from the original poster, and I've had no time to investigate, but will say that the pieces I've seen with the mark have been nice quality and appear to be mid-20th century. The Hamilton/Hamilton Silver Co., Inc. pieces I've seen (sugar/creamer sets, compotes, cigarette urns, etc.) would be of similar dating, usually seem to be of a bit lighter weight than the items with the "mystery" mark, and often have weighted bases - they also sometimes have similar two or three digit production codes. If Hamilton Silver Co., Inc. was the manufacturer, perhaps this trademark was used on their better quality items, intended to insinuate their being comparable to Danish silver.....
~Cheryl