Metal shavings in similac advanced formula.

Every time I make my baby a bottle I️ check the bottom to make sure all the formula has dissolved into the water. Recently I’ve been finding these things in her bottle. I’ll pour it out until I️ find the thing and I️ look at it. It looked like metal shavings. I️ looked up “black specks in formula” and someone said that it’s burnt formula. But then I️ looked up metal shavings and found nothing. The last one I️ saw was huge! Has anyone else experienced this? What should I️ do?