1800s antique aquamarine and diamond paste statement ring - large size

Basically my dream ring! Features old cut foiled back diamond paste, around a central blue stone - pretty sure it’s paste but no gem tester at home - aquamarine in colour, which is open at the back to allow the light.

Stones are collet / dogtooth set. Could conceivably have been worn as a man’s ring, if part of the macaroni set! Think it’s a bit too flash for a dandy but maybe.. regardless it’s a particularly large size, approx a UK U or US 10

Front face is approx 2.5cm high.

Stamped for silver, no hallmarks. 

Condition: As you can see one stone is a later, but still antique, replacement. 
Some flea bites to central stone under magnification as shown. 
Have only lightly polished, odd mark to silver.

Ring box shown is not included, but I will send in a modern jewellery pouch and boxed for protection.