18 K yellow diamond ring. This is an unusual shape, ring octagon ring with a small cushion cut yellow diamond .16 carat the total weight in grams is 1.08. This is a natural diamond. I have the certificate that will come with the ring, the size of the ring is almost a six mark. So the size seems to be a 5 3/4. Please look at the measurements on the mandrel. This is a great ring to stack with. And this is a very good prize for an authentic natural yellow diamond.