I wondered if my tap water had metals in it. A bottle of soap used to clean had water drops that eventually fell to the bottom. This is a plastic bottle, stone countertop...the water dried...then rusted.
@scottyorange where I am has really good water by national standards (we used testing kits ourselves, as I’m not very trusting of authority statements), but it still contains low levels of this and that. For drinking water, I use one of these: https://a.co/d/6DlDvfr
They are so cocksure of their filtering that they include a particulate sensor so you can see for yourself.
@MookyTroubadour water company here has water quality reports on their website. But I think this is just after it leaves the main source? They say it's an average of 50 samples...but no mention of where they were taken. I highly doubt they go much further from where they supply the water to test it. But I could be wrong.