What is this close-up picture? (WotsThat: Corroded copper pipe)

Question

What object is shown in this zoomed-in close-up photo?

TravertineZ · Accepted Answer

Corroded copper pipe. The Green Patina Actually Protects Your Water That beautiful blue-green coating that forms on old copper pipes—called verdigris—is actually nature's way of sealing the metal and preventing further corrosion, which is why Victorian-era copper pipes can still work perfectly fine after 100+ years. Ironically, this protective layer is so effective that plumbers have to actively remove it if they need to solder pipes back together!

Answer: Corroded copper pipe

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