I hesitate to reply. With all due respect. Contradicting the experts is risky if you are afraid of expressing yourself. Or too fragile to be corrected. Perhaps few will believe me when I say that that I knew the owner of the collection and there were zero marbles out of over 800 that were post 1960. The collection belonged to his father who played marbles as a child. It was passed down to him in 1983. Well before Jabo. He knew nothing about them and had no interest in them beyond asking $275. Neither of us knew the value of the collection. I have sold several thousand dollars worth of the collection with 90% of it remaining. It’s how I got started 14 months ago. I’m new. But this is not a Jabo. Not to mention that Jabo seems to be well documented and photographed in production. Someone should be able to back up their claim with a Jabo picture. Got to stick to my guns here. It’s lumpy and out of round. It’s been played. 99.99% of Jabo marbles have never been played. And never will be. That’s all I have to say. You can call me stupid, but it’s not a Jabo.