all that glistens is not gold

all that glistens is not gold

Things that have an outward appeal are often not as beautiful or valuable as they seem. I don't know if that necklace from the flea market will have the resale value you're anticipating. All that glistens is not gold, you know. A: "I want to grow up to be a movie star, then I won't have a care in the world!" B: "Just remember that all that glistens is not gold. The pressures of fame can be difficult."
See also: all, glisten, gold, not, that
Farlex Dictionary of Idioms.

ˌall that ˌglitters/ˌglistens/ˌglisters is not ˈgold

(saying) not everything that seems good, attractive, etc. is actually good, etc: Don’t imagine that because they are rich, they are happy. All that glitters is not gold.
The verbs in this idiom all mean ‘shine brightly’.
See also: all, glisten, glitter, gold, not, that
Farlex Partner Idioms Dictionary
See also:
  • all that glitters is not gold
  • all that glitters/glistens/glisters is not gold
  • glisten
  • glitter
  • (as) fit as a flea
  • fit as a flea
  • flea
  • flea in one's ear, a
  • a flea in ear
  • a flea in your ear
References in periodicals archive
All that glistens is not gold -- it might be a bubble.
The one-off course All That Glistens is Not Gold takes place on March 25.