Been refining wheel weights into ingots for better storage this past weekend. After hand sorting, some Zinc weights still made it through. Decided to take a picture to show they float. Checking metal temp a few times the temp of the pot never went above 650. If you are having suspected Zinc issues, I would suspect the pot temp is way too high. Zinc melt point is 787.2°F.
The high surface tension if molten lead will even keep the steel weights a float. The Zinc weight in this picture sat for more than 10 minutes and was still floating. Hope this helps.
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