What do you know about Gold Coin Grass? I am doing some googleing and researching on flushes and reading that this is something very helpful
I think it I read somewhere it is believed to soften the stones making it easier for them to pass. Here is a link with some testimonies of people who said other flushes did not work but using GCG they were able to pass stones.
http://curezone.com/gallstones/digest1.asp