Antique Old Mine Cut Diamond Cluster Engagement Ring.  This Victorian engagement ring features 1.39 carats of Old Mine cut diamonds which are set in 18 karat yellow gold. At the center of the cluster is a .27 carat diamond which is very dramatically prong set and surrounding it are eight (8) .14 carat diamonds. The shoulders of this ring have an interestingly cast design making use of the yellow gold which gets wider and then thins out just before the crown basket.