The final price for an old red wheelchair exceeded expectations at a Christie’s auction in London that ended on Thursday.
A mystery buyer spent about $390,000 on the wheelchair, a motorized model that had belonged to the physicist and author Stephen W. Hawking, who died in March at age 76. That is more than 15 times the pre-sale estimate made public by Christie’s.
It was among 22 items on offer from Dr. Hawking’s estate in an online auction that began on Oct. 31. All of those were sold, and the total, about $1.8 million, was seven times more than had been predicted.
“The results of this remarkable sale, with more than 400 registered bidders from 30 different countries, demonstrate the enormous admiration and affection with which Stephen Hawking was viewed around the world,” according to a statement from Thomas Venning, the head of books and manuscripts for Christie’s, and James Hyslop, the head of science and natural history.
Altogether, the items auctioned, which also included possessions of Sir Isaac Newton, Charles Darwin and Albert Einstein, were sold for more than $2.3 million.
The red wheelchair was used by Dr. Hawking during the late 1980s and early ’90s; he stopped using it when he could no longer steer it with his hands. The physicist spent most of his life steadily losing control over his muscles because of amyotrophic lateral sclerosis, or Lou Gehrig’s disease.
A bidder also spent more than $760,000 — more than double the expectation — on Dr. Hawking’s signed 1965 Ph.D. thesis, “Properties of Expanding Universes,” about the origins of time and space.