Thank you for your bug-report! I'll try to investigate what causes the resource jump!
By any chance, do you recall what items you have equipped in your body-grid when the metal jumped and dropped?
EDIT: Found and discovered the bug, I will update the web-demo as soon as I can to fix this, as well as other feedback from other players; again, thank you so much for the help!
EDIT-2: fixed the bug, should no longer happen!