B.S. MARBLE

I took my 10 yr old son Ben to a yard sale last week. He collects antique and vintage handmade marbles... We found this one. What's the chances of finding an old handmade marble with your own initials on it at a yard sale? The lady having the sale had no clue she had it placed out, it was hidden in the bottom of a bowl. She was sweet and just gave it to him. It's by far Ben's newest favorite!

I'm an antique hound, but really don't have any knowledge in the marble department. Although, I am the one that got my son hooked on marbles as I love art glass and thought this would be a fun way to get him started on collecting, needless to say, he's hooked.

Any info about this marble would be helpful. The photo is poor, but the marble is white with what I believe to be ox blood red.