All that glitters is not gold
Meaning: The attractive exterior of something is not a good indicator of its real nature. It may look valuable, but not be valuable.Note: glitter (verb) = shine with reflected light | gold (noun) = a yellow precious metal
Origin: This is an old saying and has existed in various forms for many centuries, possibly dating back to Aesop. It is found in Chaucer in the form "Hyt is not al golde that glareth." The modern form of the saying is a derivative of a line in Shakespeare's play The Merchant of Venice which uses the word "glisters", a 17th-century synonym for "glitters": "All that glisters is not gold"
The saying "All that glitters is not gold" reminds us that something glittering