Featured Can you tell me anything about the "Sterling" bird brooch?

Hello all, happy Friday! Another item mixed up in an auction lot. It is a brooch marked Sterling and patent pending- BUT I tested it and it really doesn't seem to be testing for silver. Do you think it could be 800 perhaps or lower? or a faker? It's not magnetic, pretty lightweight. Measures 2.5" across. The back is a little unusual, I haven't seen that kind of pin contraption before. What age could it be? Many thanks for input as always

 

Here is one similar.. but the back pin is different: https://www.rubylane.com/item/58548...ZTbcFiyvz76I1p287Tw0v4VEro8_VschoCB8UQAvD_BwE

 

Great find, thank you! I wonder why it doesn't appear to be testing as silver with my kit? Maybe time for a new batch lol

 

Lovely. Interesting clasp on it, I’ve not seen one like that before.

 

Thanks! Me either

 

Elen's is marked "design patent pending". The pin on Ruby Lane is marked patent 2.327.138.

I tried to find it on the Google patents website but failed. Maybe someone else will have success.

 

Oh, well spotted!

 

I did a quick search and found this which is likely for the unusual joint mechanism on the back? Perhaps this brooch is missing part of it. The patent is in 1943 so perhaps mine is late 30s, early 40s? Or perhaps I have found the wrong patent entirely lol