"Heart of gold" is an idiomatic English expression indicating that a person has a kind, generous and caring personality. Its meaning is rooted in traditional symbolism relating to the properties of gold. It is sometimes used to indicate a contrast between a person's appearance and behavior by suggesting that the individual has a good heart underneath an exterior that suggests otherwise.
The first recorded use of the phrase occurs in a play from 1553, "Ralph Roister Doister." This farce, regarded as the first comedy written in English, concerns the unsuccessful efforts of Ralph, a buffoon, to woo the beautiful Christian Custance. Among the other endearments Ralph bestows on her is "my heart of gold." In its first use, the term clearly describes a woman being praised for her excellent personality, as well as describing Ralph's love for her.
In medieval symbolism, gold represented the pinnacle of luxury. Due to its rarity and value, it was considered the noblest of all metals and thought to represent positive qualities of the human spirit such as generosity, justice and courage. The symbolic value of gold can be seen in other expressions such as "golden age," referring to a lost age of greatness, or "golden boy," signifying a promising youngster.
Like gold, the heart has played an important role in symbolism throughout history. Medieval thinkers believed the heart to be the seat of emotion and passion. This symbolism permeates modern language in phrases such as "matters of the heart" or "to have a good heart."
By combining these two potent symbols, the phrase "heart of gold" suggests a person with a kind, generous and noble personality. The contrast with external appearance appears especially in phrases describing fictional characters. A particular type of leading man is commonly known as the "scoundrel with a heart of gold" while the "hooker with a heart of gold" is a well-worn literary trope.
The phrase has permeated literature, the arts and popular culture. It appears as the title of numerous albums and songs, notably a 1972 hit by Neil Young, which became the title of a documentary about him. It was also chosen as the name for a fictitious spaceship in The Hitchhiker's Guide to the Galaxy by Douglas Adams. Two novels with this title were released in 2000 alone. A film festival in Queensland, Australia is known as the Heart of Gold International Short Film Festival.