I have had those little bits of yellow before. They are larger than "chaff" the flakes of cholesterol that resemble sawdust; and smaller and paler than true stones. I believe it is small bits of cholesterol that has not been colored by biliary pigments. There is a small chance they are parasite fragments, but I still think its cholesterol that has not formed into stones. If you feel good after flushing, then you can consider it a good flush.