Butterfly brooch with 'moving' wings

[Maria L]

Hi
I was offered this beautiful 18k solid gold butterfly brooch with 'moving' wings (the top layer of wings can move/vibrate, could see the springs underneath) from a dealer. He believed its from the 60s. Has anyone got more information about this kind of brooch please?

Many thanks .

 

[stracci2000]

It's gorgeous!
These are called "en tremblant"

 

[Maria L]

It's gorgeous!
These are called "en tremblant"

Thank you so much!

 

[RRfromR]

It's gorgeous!
These are called "en tremblant"

Yes!! OP, take a video for us please.