Another misquotation, the original being "All that GLISTERS is not gold"
Since glisters and glitters mean roughly the same thing the latter word has become normally used in place of the semi-archaic "glisters."
Commonly used by all sorts of people, many of whom would not realize it comes from "The Merchant of Venice"
Tolkein even paraphrased it in Lord of the Rings, as part of a poem describing Aragorn.
