I was fortunate enough to get a 10,000 count crate of mixed Akro Agates many years ago. Mixed in were mostly corks, but 100s of flinties, flintie style marbles, moonies, unique patches, royals and a few hundred 9/16" clear uranium glass marbles. The variety of colors in the flintie styles were amazing.
In the pics below you will see many had the dark or black 'smile' line in them instead of the typical clear point. If you look closely some have slight corks, some are patches but all in the flintie colors. The box set I made up of my favorites. Many I would not known were Akro if they didn't come out of the crate.