A small selection of the massive National Geographic Society archive — 240 pieces spanning from the late 1800s to the present — will be sold at Christie's in December at an auction expected to bring about $3 million, The Associated Press reports.

Among the items are some of National Geographic's most indelible photographs, including that of an Afghan girl, a portrait of Admiral Robert Peary at his 1908 expedition to the North Pole, a roaring lion in South Africa and the face of a Papua New Guinea aborigine.

Paintings and illustrations include N.C. Wyeth's historical scene of sword-fighting pirates, Charles Bittinger's view of Earth as seen from the moon, and Charles Knight's depictions of dinosaurs and other prehistoric animals.

They are being auctioned "to celebrate our legacy .... and to give people a chance to buy a little part of this great institution's history," said Maura Mulvihill, senior vice president of National Geographic's image and video archives.

"We think of ourselves as the unsung fathers of modern photojournalism," she added. "I don't think people are aware of what a massive instructive archive this is."

Proceeds from the Dec 6 auction, just weeks before National Geographic's 125th anniversary, will go for the promotion and preservation of the archive and "the nurturing of young photographers, artists and explorers ... who are the future of the organization," Mulvihill said.

National Geographic sponsors and funds scientific research and exploration through its official journal, National Geographic Magazine, which reaches 8.8 million people worldwide in 36 countries and in 27 languages. The society reaches millions more through its National Geographic Channel, books and other sources.