Tried looking this up and found lots of disagreement about oxide finish and triangle B markings. I’ve been using it for a paperweight for ever. What can you Much-respected experts tell me about the age of it?
That looks to me like a painted finish. Alloy Artifacts suggests a production date of 1915-1926, and has a photo of the same "auto" (smaller version would be "bicycle") wrench. Scroll down to Model G 8 Inch Auto Wrench:
Okay thanks! I got sidetracked with discussions about ones marked “G”, and whether or not that means government, etc. I’ll clean and oil it and take better care of it [emoji17].