They travel for hundreds of miles to visit shops like mine and then insist that the going price is only fifty cents a scoop. Of course, button collectors are worse, having once been marble collectors but upon losing their marbles, started collecting buttons. The truth is, if pressed hard enough by the prospect of losing a marble to another collector, they will pull out their wallets and peel off several twenty dollar bills for the right specimen. As with many things, marbles are not my field of expertise. The bigger the better.
Some marbles are two inches in diameter.
Older marbles of this size are always of value. Condition is not everything, and marbles can be polished. But premium prices are paid for unpolished good marbles with no nicks. The best marbles are those with distinct designs with uniformity, not just a blob of color. Look for a lacy column in the center and an even swirl in the outer glass or designs similar to that of a nice paperweight.