A remarkable set of rare medals awarded to explorer Sir Ernest Shackleton for his Antarctic expeditions are up for auction.
Shackleton was the most decorated polar adventurer and the set includes the Royal Geographic Society's Silver Medal, awarded for his part in the landmark British Antarctic expedition aboard Discovery, valued at £20,000 to £40,000.
The group of 14 lots will be sold at Christie's South Kensington and central to the sale will be the medal he received when made Commander of the Royal Victorian Order for reaching the farthest South ever explored, estimated to sell for £20,000 to £30,000.
He was ultimately beaten in the race to become the first explorer to reach the South Pole by Roald Amundsen in 1911 so, in 1914, he began instead to prepare for the Imperial Trans-Antarctic Expedition aboard Endurance, the first land crossing of the continent.
This year marks the 100th anniversary of the sinking of Endurance, which was crushed by ice and left the crew marooned on Easter Island.
Shackleton's Chilean Order of Merit, recognising the rescue and survival of all Endurance's crew, will be an important lot, expected to reach £4,000 to £6,000.
The rest of Shackleton's awards up for auction in Christie's Travel, Science and Natural History sale consist of British and foreign decorations gathered during the career of one of Britain's principal polar explorers.