u/Reasonable-Art-7643

I've had this engagement ring passed to me from my grandmother. Can anyone shed light on the stones/metal?

Posted originally on r/cadmiumglass as that's what I originally thought it was intended to be, however I've been lead to believe it's manganese instead? I'd bought it for 50AUD and whatever it may be it still has a place in my glassware cabinet, but I'd like to know any other information about it as well.

Just a few pieces I've collected so far from antique stores and hoping to fill out the case more

First post. I picked this up for 50AUD recently from a nice little second hand store. Marked as cadmium glass so I thought I'd take the plunge but I'm thinking it may not be?