I heard before that if a ring has 6 prongs then it makes the diamond look smaller than 4 prongs. is that true?
I think it depends on the size of the stone. On a smaller diamond, the amount of metal next to it may overwhelm it. The six prongs cover up more of the side of a stone and thus might give it a dwarfed appearance. On larger stones, I don't think it makes a difference really.