PARIS — A U.S. charitable foundation said Wednesday that it was the anonymous bidder that paid $530,000 for 24 Native American masks in a Paris auction and will return them to the Hopi Nation in Arizona and the San Carlos Apache tribe.

“These are not trophies to have on one’s mantel,” said Gregory Annenberg Weingarten, director of the Los Angeles-based Annenberg Foundation. He added: “They do not belong in auction houses or private collections.”

Twenty-one vividly colored masks made of leather, horsehair, wood and feathers bought at Monday’s auction are being returned to the Hopis and three hood masks to the San Carlos Apaches.

It was a happy ending for the Hopi tribe following a series of legal setbacks in efforts to delay the sale of the masks, arguing that they represent ancestral spirits and shouldn’t be sold. The tribe has said it believes the masks, which date from the late 19th and early 20th century, were taken illegally from a northern Arizona reservation in the early 20th century.

The U.S. Embassy had also called for a delay so that tribal representatives could come to France to identify the artifacts and investigate whether they have a claim under the 1970 UNESCO Convention on the Export and Transfer of Ownership of Cultural Property, to which both France and the U.S. are signatories.

“Our hope is that this act sets an example for others that items of significant cultural and religious value can only be properly cared for by those vested with the proper knowledge and responsibility. They simply cannot be put up for sale,” Sam Tenakhongva, a Hopi cultural leader, said in a statement Wednesday.

The Drouot auction house said the total sale was for $1.6 million, including a sacred “Crow Mother,” a menacing Hopi mask with billowing black plumes, which sold for nearly twice its expected value at $171,000.

Pierre Servan-Schreiber, a lawyer who represents the Hopis, told The Associated Press that he’d personally bought one mask to return to the tribe.

In a similar dispute in April, a Paris court ruled that such sales are legal, and around 70 Hopi masks were sold for some $1.2 million, despite protests and criticism from the U.S. government and actor Robert Redford.