Rock icon Freddie Mercury pre-auction exhibition opens in London

On stage with the rock band Queen, Freddie Mercury held the world in the palm of his hand. Now, a London exhibition shines a light on his private world.

Sotheby's has unveiled Freddie Mercury: A World of His Own, a public exhibition of over 33,000 items that belonged to the superstar. The exhibit will be followed by six auctions starting next week and continuing throughout September.

The collection includes handwritten drafts of Mercury's songs, as well as stage costumes, furniture and decorative art, stored for over three decades at Garden Lodge, Mercury's home in London.

"Mary Austin, lifelong companion of Mercury, has been the guardian of all of these things for over thirty years and the time has come to start the next chapter," Sotheby's told ABC News. "She wants to hold the sale now so she can oversee it herself and share this new side of Freddie Mercury with the world."

All of Sotheby's 15 galleries on New Bond Street in London are dedicated to a different aspect of Mercury's life, recreating the original displays in his home. "It is the highlight of my career to present this to the world," David Macdonald, head of Single Owner Sales at Sotheby's London, told ABC News.

Some exhibit items are immediately recognizable from Mercury's performances, such as his signature red cloak and crown, or the 'Mercury wings' he stitched to his stage costumes. However, the majority of the items were seen only by those closest to the music icon.

The top lot, with an estimated value of between $2.5 million and $3.8 million, is Mercury's treasured Yamaha G2 Baby Grand Piano, which he acquired in 1975 and on which he composed many of Queen's most recognizable songs, including the enduring hit "Bohemian Rhapsody," released that same year. Sotheby's said it was difficult to estimate the instrument's value: "This object was at the heart of his unparalleled journey. It's like Da Vinci's paintbrush."

Also high in value are the handwritten drafts of Queen hits, providing rare insight into Mercury's songwriting process. The "Bohemian Rhapsody" lyrics draft alone is estimated to be worth between $1 million and $1.5 million.

Another more private item is the multicolored 1941 Wurlitzer jukebox that Mercury kept in his kitchen and on which he played music as he was having breakfast. Dubbed 'The Peacock' due to the animal design that shimmers when the still-operational jukebox is lit up, the item is expected to sell for between $19,000 and $32,000.

Mercury also collected fine art. As a curator, Macdonald was impressed to discover that Mercury personally chose everything in his collection, telling ABC News, "Freddie the collector was careful, coherent and curious." Offerings from Mercury's collection feature works by 20th century masters including Picasso, Henri Matisse, Marc Chagall and Georges Braque, as well as a James Tissot work from 1880, valued at between $511,000 and $766,000.

For Freddie Mercury fans of more modest means, there are smaller items going on the block, including a collection of chopsticks, a Tiffany silver seam ripper, membership cards to London clubs, a red-painted vanity mirror, a cookie jar and many cat miniatures, all expected to sell for around $130 or less.

Auction proceeds, which are projected to exceed $12.7 million, will be split between the Mercury Phoenix Trust, dedicated to fighting HIV/AIDS, and the Elton John AIDS Foundation. Mercury died of AIDS in November of 1991 at age 45.