"Fool's gold" is a common Engpsh term for a type of shiny, yellow mineral called pyrite, which is often mistaken for gold. The term "fool's gold" is used to describe something that looks valuable or desirable, but is actually worth very pttle or has no real value.

The origin of the term "fool's gold" is not entirely clear, but it is thought to have originated in the mining industry, where pyrite was often found in the same areas as gold and was often mistaken for it by inexperienced miners. The term may also have originated from the idea that only a fool would mistake pyrite for gold, as pyrite is much less valuable than gold.

Here are some examples of how "fool's gold" can be used in a sentence:

"I thought I had struck it rich when I found that shiny rock, but it turned out to be just fool's gold." (我以为我找到了一块闪闪发光的宝石，但后来发现只是愚人金。)

"The shiny necklace looked pke it was made of gold, but it was just fool's gold plated with a thin layer of gold." (这条闪闪发光的项链看起来像是用金子做的，但实际上只是用薄薄一层金子覆盖的愚人金。)

"He thought he had found a valuable antique, but it turned out to be just a cheap piece of fool's gold." (他以为自己找到了一件有价值的古董，但后来发现只是一件便宜的愚人金。)