Victorian 18ct Gold Three Stone Diamond Rub Over Set Ring

This is the largest rub over diamond ring that we have ever come across.  It is 18ct gold and was made circa 1880.  It has been set with three well matched old European cut diamonds that have an approximate total weight of just under three carats. Rub over settings help protect the stones from knocks and bumps but also from grease and dirt and the Victorians were particularly brilliant at making these settings.  The diamonds are a high colour and a good clarity. It would be an amazing engagement or dress ring