Finding this reminded me I need to get some more old clay marbles in stock, which I will do, and makes me think it's time to get serious about actually playing marbles as well! (I love the image of kids carrying around their marbles in bags like this, ever ready for a match in an alley or driveway, and with the real stakes of winning one's opponents marbles for keeps.) But of course plenty of other things this would be good for carrying too. Soft leather, nicely worn, with drawstring for closing it tight.
5 5/8" t x 4 1/4" diameter when open wide. Very good condition c. 1940s-50s. Stitching holding tight.