RR Auctions in Boston is offering a royal bargain.

At its September 17 Remarkable Rarities Auction, the house is offering a unique collection of 14 behind-the-scenes photos from the wedding reception of Princess Diana and Prince Charles at Buckingham Palace on July 29, 1981, following the ceremony at St. Paul’s Cathedral. The minimum bid is $300, which works out to about $21 per photo.

According to the online catalogue entry, the photos originate from the collection of an unnamed assistant to English photographer Patrick Lichfield, whose connections—he’s described as being of “peerage descent”—allowed him access to the Royal Family.

The collection consists of seven black and white 10″-by-8″ photos, seven color satin-finish 7″-by-5” photos and the pass used by Lichfield’s assistant for access to the palace.

Six of the photos depict Princess Diana posing, in her wedding dress, with family members and her wedding party, which included Queen Elizabeth, Prince Charles, Princess Anne, Princess Margaret, and Princess Andrew. Three photos show Princess Diana’s youngest bridesmaid, five-year-old Clementine Hambro. Another shows Diana smiling as Prince Andrew leans over to talk to Clementine. Others show Diana and Charles from behind as they greet crowds from the balcony of Buckingham Palace.

The pass reads: “Admit Miss…to Buckingham Palace Side Entrance on Tuesday, 28th July at 2:00 p.m. Remarks: To install lighting in the Throne Room for Wedding Group picture.”

The images are accompanied by a detailed letter of provenance identifying the subject in 12 of the 14 photos as well as offering further specifics: “I was the photographic assistant to Lord Patrick Lichfield…the only photographer allowed to take informal photographs of the royal family and their guests when they returned to Buckingham Palace…for the wedding reception. These are original prints…. To my knowledge, none have ever been published. Very few people have ever laid eyes on them.”

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