A letter from Prince Charles describing a Swiss skiing accident that killed his friend, Major Hugh Lindsay, failed to sell at auction on Thursday.
It was among documents being auctioned at Ludlow Racecourse, Shropshire, by Robert Marrington, ex-superintendent of works at Sandringham House, Norfolk.
Charles says of the 1988 avalanche at Klosters: "I find it hard to understand why I survived and he didn't."
The letter had a guide price of between £250 and £350.
The 1988 avalanche killed Major Lindsay, a former Queen's equerry, and badly injured the mother of socialite Tara Palmer-Tomkinson, Patti, as the pair skied off-piste with Charles and his guide Bruno Sprecher.
Document specialist Richard Westwood-Brookes, of auctioneers Mullock Madeley, said other royal ephemera such as original tickets to the Queen's wedding in 1947 sold well.
A series of letters written by composer Sir Edward Elgar, including one concerning the copyright of his most famous work, The Dream of Gerontius, sold for a total of £2,300.