The Marbles were an English rock duo that consisted of Graham Bonnet and Trevor Gordon, who operated between 1968 and 1969. Their only well-known singles were "Only One Woman" and "The Walls Fell Down". They also became associated with the Bee Gees members Barry, Robin and Maurice Gibb at that time.

"Only One Woman" reached number 5 in the UK Singles Chart in November 1968.^[1] The duo disbanded in 1969. Shortly after their split, in 1970, they released their only self-titled album.

Bonnet and Gordon are cousins. They were born in Skegness, Lincolnshire, England,^[2] although his webpage, In Memory Of, states Gordon was born 18 May 1948, in Blackpool, Lancashire, England. While Bonnet stayed in England, Gordon grew up in Australia where he met the Bee Gees for the first time in 1964, on which Gordon recorded "House Without Windows" and "And I'll Be Happy"; both songs were written by Barry Gibb. In 1965, Gordon recorded two other Barry Gibb compositions: "Little Miss Rhythm and Blues" and "Here I Am". Gordon returned to England in 1966 and recorded one single as 'Trev Gordon' then returned to Australia, and returned to England again in 1967 to join Graham's band the Graham Bonnet Set. In 1968, they became the Marbles, and signed a recording contract with the Australian record label impresario, Robert Stigwood.^[3] Although Stigwood signed only Bonnet and Gordon, drummer Steve Hardy from the Blue Sect/the Graham Bonnet Set, continued to work with them. Hardy's vocal work was on the song "By the Light of the Burning Candle" (with vocals by Gordon originally, later, the song was reworked in July 1968 with Bonnet on vocals).^[4]

They were befriended by the Gibb brothers Barry, Robin and Maurice Gibb of the Bee Gees who wrote six songs for them, and provided some backing vocals. "Only One Woman" was released in the UK and the U.S. in August 1968; the single reached the top 5 in the UK and was their biggest hit.^[4] Following the release of the group's debut single, Bonnet made a remark to a reporter as to "Only One Woman" being a bit boring, angering Barry.^[5] Their second single, "The Walls Fell Down" only reached number 28 on the same chart.^[1] But in the Netherlands it was more successful, where it reached number 3 in their top 40 in April 1969. Their third single, "I Can't See Nobody", a cover of the 1967 Bee Gees song which was arranged by Jimmy Horowitz, was only released in Europe, except in the UK. By 1969, the Marbles had split. Their fourth and last single, "Breaking Up Is Hard to Do" (third in Britain) did not chart internationally. "I Can't See Nobody" was chosen as the B-side in the UK, "Daytime" in Europe and "Little Laughing Girl" in America. In August 1970, Cotillion Records released their only self-titled album in the United States.^[6]

After the split, Bonnet started a lengthy solo career. From 1979 to 1980, he was the lead singer with Ritchie Blackmore's Rainbow.^[2] While Gordon released one solo album Alphabet, he later became a music teacher and died in 2013 in London.^[7]