A novel about gold on the outside gave an entire era its name.
In 1873 Mark Twain and Charles Dudley Warner published The Gilded Age: A Tale of To-Day, a satire of greed and political corruption in post-Civil War America. The title is the point. Gilding is only a thin layer of gold over something cheaper, and the name stuck to the whole period.
A thin layer. Over everything.
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