I've owned this bowl for several years. It has absolute stunning hammering on it (better than much Roycroft). The bowl is 6.5" wide and the patina is reddish, like some of Dirk Van Erp's work. Any suggestions as to who made this high quality bowl, but didn't sign it, are welcomed. Thanks!

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Welcome to the forum,

Your copper bowl has great appeal and a wonderful patina. I doubt if we will be able to identify it's maker. Several makers did not sign their work and others used paper labels that fall off in time.

I can tell you that the bowl was spun on a lathe to create it's basic shape and the hammer marks were applied to mimic the process of hand raised work. The chased lines are well done. My first thought was that perhaps it was the work of Han Jauchens or Fred Brosi. I ruled it out since their hammer marks are more uniform with machine like precision. Your bowl shows a bit mor eratic blows of different weight and a bit more random.

A beautiful piece for any collection. Congratulations and thank you for sharing it with us.