just check d3 guide and found that highest grade gem in ros will need 177147 flawless square gems to make.

use ruby as example:

3 Radiant Star Ruby = 1 Marquise Ruby

3 Marquise Ruby = 1 Imperial Ruby

3 Imperial Ruby = 1 Flawless Imperial Ruby

3 Flawless Imperial Ruby = 1 Royal Ruby

3 Royal Ruby = 1 Flawless Royal Ruby

i think blizzard encourage players to form in clans and play as community, if not really not possible to make it alone.

if ros drop Marquise then still can accept, but then i cant understand why ppl still buying gems from ah? high price summore