GetReader’s DigestsRead Up newsletterfor more cleaning, humor, travel, tech and fun facts all week long. Over time, copper sinks, pots and pans may lose their luminance. They can also turn ...

but accidentally using a harsh chemical cleaner on a sealed piece can strip the seal off completely. How do you know what you’ve got? “A copper sink is usually unsealed because it’s ...

In other words, knowing how to clean a porcelain sink isn’t the same thing as, say, knowing how to clean a copper sink.