Ivan, I'm sure you now know me well enough to answer that if I incurred such dilemma. Still, in buying pre-owned student quality, such wouldn't surprise me and I think you've been around long enough that it wouldn't surprise you either. However, if it worked I wouldn't expect an escalation in damage by vacuuming with a Shop VAC. Mine is 10 HP and has picked up tractor nuts buried in the sawdust in our old shed. Too, such deters collateral injury or property damage and the turn-around time is less than 5 minutes. I just think it's more likely to be a super ball or a cat's ball than a marble in these times, but when I was in 5th grade marbles were prolific in about every boy's pocket. Alas, the last marble manufacturer in the U.S. (Pennsboro WV) is now defunct and now all on the market are imports. Small flower arranger marbles are very effective Whamo slingshot ammo. I've some fractured old marbles now cemented to our table ceramic Christmas tree. Yes, they've good uses ... and they're trouble. Orthopedic surgeons can tell you of many hip replacements caused by such loose on the home flooring.