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What mineral would likely cause boiled water to turn brown and --?
a dark grey crust (likely oxidation) to form on a stainless steel sauce pan?
The pan has never been used except to boil water and the lid is always on except when adding/deleting water.
Water is from a well and has passed the normal tests (bacteria and clarity).
Reservoir is basaltic in nature so likely that the water is heavily mineralized.
I don't believe it is dangerous in any way - just curious.
The crust builds for a while then chips off and is near impossible to scrape off (without damaging the pan)
1 Answer
- 1 decade agoFavorite Answer
My best guess is Calcium- most likely Calcium Carbonate. It is found in most tap water, especially from artesian wells. It is usually found with Magnesium and there are traces of sodium, potasium, etc.. (all carbonates). As you boil water, these minerals concetrate and precipitate out of water. They appear at the interface of the water and the pan. They are also more soluble at high temperatures and when the water cools they crash out on the walls of the pan. Don't worry, they are completely harmless and actually good for you!
