I’m actually pretty curious about this myself, as I have two stamped cuffs with the same hallmark. I had also come across the hallmark for Edison Cummings in Hougart’s book, but after looking up his work I decided it didn’t match. He is an award winning modern artist who does a lot of tufa casting, inlay, and Loloma-inspired work. Could he have made my very simple stamped cuffs? Maybe. Hougart’s does say it was an early hallmark, so maybe his work was a lot different then. But I have a feeling he didn’t. I’m not sure about your ring either.
There was another thread on here with the exact same hallmark posted a while ago. They never got an answer. I tried to find the thread just now and couldn’t.