Featured Help with drop earring hinge name and era?

Hello..

What do you call the hinge on this drop earring set? What decade was this started?
They are 925 raw ruby ..

 

They are fairly recent Indian made, and really nice.
The concept of hinged jewellery is centuries old, so the presence of a hinge is not an indication of a certain period

 

Thank you, how can you tell fairly recently made?

 

The style is recent. India has been making a lot of these, all really attractive, but not old.