Marilyn Monroe fan with the world's largest collection of her costumes, clothing and jewelry is set to auction it all off, because he feels it is 'time to share this with the world' 

Marilyn Monroe's wealthiest fans will undoubtedly be getting their checkbooks ready this fall as the world's largest private collection of the star's iconic film costumes, gowns, personal clothing, jewelry, and other property will be hitting the auction block along with original photographs and film posters of the late actress. 

Unforgettable stage costumes from Marilyn's films Some Like It Hot and There's No Business Like Show Business are expected to fetch up to $400,000 each as the entire collection owned by David Gainsborough Roberts is conservatively valued at around $3 million ahead of the November 19 sale by Julien's Auctions. 

'It is now time for me to share this with the world,' Mr Gainsborough Roberts said of his memorabilia, which has been stored at his home in Jersey, in the Channel Islands.

Memorabilia: The world's largest private collection of Marilyn Monroe's film costumes, gowns, personal clothing, jewelry, and other property will be hitting the auction block in November 

Iconic number: Highlights of the auction include the sheer black and nude beaded cocktail dress (right and left) Marilyn wore in Some Like it Hot in 1959 while singing on top of a grand piano 

Bling ring: Marilyn's jewelry is also being sold, including the paste, triple drop, mixed cut fringe earrings (right) she wore to the world premiere of The Seven Year Itch on June 1, 1955 in New York City

The legendary actress was found dead in her Brentwood home in Los Angeles in 1962 at the age of 36, and the collector noted that Marilyn would have turned 90 years old this June. 

Mr Gainsborough Roberts, who is in his 70s, purchased his first piece of Marilyn memorabilia at a Christie's auction in South Kensington in 1991 and has since amassed what is widely recognized as the largest private collection of the movie icon's film costumes in the world.

'I was buying certain Hollywood stuff - not with any idea of buying Marilyn - when, in 1991, I bought her dress from [1954 movie] There's No Business Like Show Business. The sale became such a big smash hit. It got in the papers and everybody seemed to be talking about it,' he said in a previous interview with Just Collectors.

'That was how it started: April 29, 1991,' he added. 'It was a day that changed my life - and goodness knows I had no intention of it doing so.' 

Famous faces: Marilyn is pictured with actor Don Murray in this still from the 1956 film Bus Stop 

Decadent design: The green satin leotard the actress wore in Bus Stop could sell for up to $100,000

Famous curves: The pink halter-style wiggle dress made for Marilyn for the Rose Loomiss thriller Niagara is at an estimated starting price of $30,000 to $40,000

Fashion star: Other items up for auction include the star's cream Castillo for Jean Lanvin gown (left) and an embellished costume worn by Marilyn in the 1954 film There is No Business Like Show Business (right) 

Highlights of the auction include the sheer black and nude beaded cocktail dress Marilyn wore in Some Like it Hot in 1959 while singing on top of a grand piano. 

The beloved comedy won best picture at the Golden Globes in 1960, while Marilyn won a Golden Globe for her portrayal of Sugar Kane. 

Marilyn wore the stunning dress featured in the auction while singing I’m Through With Love in a scene from the award-winning film. 

Julien's predicts the glittering ensemble that is undoubtedly a treasured piece of film history will sell for $200,000 to $400,000. 

Another famous costume, the silver and white beaded dress Marilyn wore in the 1954 musical There's No Business Like Show Business is estimated to go for $100,000 to $200,000, while the green satin leotard she wore in Bus Stop could sell for up to $100,000, according to Julien's. 

Red hot: Marilyn and her co-star Jane Russell are pictured wearing matching sequin gowns from the 1953 film Gentlemen Prefer Blondes

Co-star: The ruby red sequin embellished figure-hugging gown worn by Jane alongside Marilyn in the opening scene of Gentlemen Prefer Blondes is expected to fetch $30,000 to $50,000

Large lot: The pearl and simulated diamond costume earrings worn by Marilyn in the 1953 film How to Marry A Millionare (left) and her personal black fishnet pantyhose by Challenge (right) are also available

Star power: Marilyn wore a black gown and fur stole while attending the premier of The Rose Tattoo with Marlon Brando in New York City in 1955

Classic dress: The black evening gown she wore to the premiere has a starting estimate of $50,000 to $70,000

Highest honors: Marilyn's New Faces award is another one of the many personal items from the lot 

Other highly-coveted items include the sequin black gloves she wore in The Seven Year Itch, the star's cream Castillo for Jean Lanvin gown, and the pink halter-style wiggle dress made for Marilyn for the Rose Loomiss thriller Niagara.

Even the costume jewelry worn by Marilyn is expected to sell for thousands of dollars at the auction. 

Bidding on a pair of paste, triple drop earrings worn by the actress to the world premiere of The Seven year Itch on June 1, 1955 in New York City is expected to reach up to $100,000. 

And unsurprisingly, the small everyday items of Marilyn's also come with big price tags. 

While the film star's black fishnet pantyhose by Challenge are expected to be sold for $600 to $800, the sterling silver money clip she gifted Harry Roberts, a soundman at 20th Century Fox, is expected to go for $3,000 or more. 

On set: This cream colored Karamís Stetson worn by an extra in the rodeo sequence of Bus Stop is autographed in black ballpoint pen by 11 members of the cast and crew of the film, including Marilyn

Generous: The cigarette box (left) and the money clip (right) Marilyn gifted Frankie Vaughan and Harry Roberts, respectively, are expected to go for up to $6,000 each 

Beautiful: These are the costumes Marilyn donned while portraying 19th century actress Lillian Russell for a feature in a 1958 issue of Life Magazine (left) and in the film There is No Business Like Show Business (right)

Always glamorous: Marilyn famously donned these gloves in the beloved film The Seven Year Itch 

Another present from Marilyn, a rectangular silver tone presentation cigarette box that she had given to Frankie Vaughan at the end of filming Let's Make Love has an estimated price of $4,000 to $6,000. 

The personal message inscribed on the lid reads: 'Dear Frankie, It was really wonderful working with you. Best Wishes, Marilyn.'   

'Marilyn Monroe is one of the biggest and most endearing screen icons of our time,' said Darren Julien, founder and CEO of Julien’s Auctions in a statement. 'We are so honored to be working with David Gainsborough-Roberts with his incredible collection of Marilyn Monroe artifacts. 

'He has meticulously archived so many important aspects of Marilyn’s career and personal life.”

Unsurprisingly, Marilyn is one of the most sought-after celebrities for collectors, and the billowing ivory 'subway' dress she wore in The Seven Year Itch sold for a stage costume record of $5.5 million in 2011. 

The auction, to be held in Los Angeles on November 19, will be preceded by exhibitions of key pieces aboard the Queen Mary 2 ocean liner in August, and in London, Los Angeles and other cities.

Fancy: A custom made silk blouse worn by Marilyn in the 1960s film Let's Make Love (left) and a 19th century-style bodice that she modeled in a 1956 photo session (right) are both estimated to sell for up to $40,000

Collector's dream: The wool skirt Marilyn donned in Let's Make Love (right) is expected to fetch for up to $20,000, while a costume design worn in her Niagara test shots (left) may go for up to $40,000

Big money: The billowing ivory 'subway' dress the actress famously wore in The Seven Year Itch sold for a stage costume record of $5.5 million in 2011