I have been searching for 3 weeks on what type of marbles I have , and it is very time consuming. I would like to sell my collection. I know I have some old marbles. Some worth clear pontil s. A few of MFChristensen. A lot of vitro agate. And many many more. Patches, rainbos , Bennington s. Various others. I believe I may have a MF baby blue -5/8 marble that is a collector item. Heck I really am just learning about marbles been collecting a year now. Ready to sell all of them. Anyone interested????