The symbolism of buckle rings varies between sources but some say that wearing a buckle ring was believed to guard the wearer, almost like spiritual armour.
Others say that Victorians sometimes used buckles in mourning pieces to signify:
Remaining connected to a loved one
Their presence still being “fastened” to you
Whatever the meaning for you, this piece is truly stunning. 
Size N/6.75
6.4grams
Diamonds: old cuts- approx 3.1mm and 2.9mm