#1. “dug marbles” These were either discarded as “non production types” (experimental) or “discards’” (those that did not meet general production standards)
#2 There are many collectors that sell and few sellers that do not collect. This hobby/addiction takes too much research to just sell. If you find an informed seller—he/she is a collector of one type or another that is she/he willing to part with one type to get cash for another that he/she collects?
There are many collectors that have turned into great sellers because of the knowledge that they have collected over the years along with the followers that they have achieved over the years because of their reputation. These sellers will sell yours for you with a kickback of course.
#3 Natural stone agates were the one to have over any glass back in the day. Glass out priced them and the glass marbles became more popular because of the price and as far as I have researched, the bright colored “solids” were the most popular after the demise of the stone agates.
I appreciate all opinions on this subject, these are my personal observations from the research that I have done.
Marble—On!!