Gary Ross Dahl, an American advertising executive who started a pop culture sensation when he created the Pet Rock in the 1970s, has died at 78.
Packed in a cardboard box with “breathing” holes, the stones sold for $4 (£2.67) and came with an instruction pamphlet for “care and feeding”.
By the time the fad ran its course, Mr Dahl estimated he had sold 1.5 million of them.
Unlike cats and dogs, the Pet Rock required no commitment.
Mr Dahl died on 23 March of chronic obstructive pulmonary disease, his wife Marguerite Dahl said on Tuesday.
“I think the Pet Rock was just a good giggle. Everybody needed a good laugh and the media ate it up,” Mr Dahl told the Houston Chronicle in 1999.
The idea started as a joke that Mr Dahl made while drinking at a bar with friends, the New York Times reported.
The rocks made their debut in 1975 and soon were featured on the “Tonight Show” and in hundreds of newspaper articles. Newsweek called the rocks “one of the most ridiculously successful marketing schemes ever.”
“If, when you remove the rock from its box it appears to be excited, place it on some old newspapers,” the instructions stated. “The rock will know what the paper is for and will require no further instruction. It will remain on the paper until you remove it.”
Mr Dahl said the rocks made him rich but without a trademark on the idea imitators quickly uncut his business.
He never matched his initial success with his later projects. He said his pet rock fame occasional brought unwanted attention from would-be inventors.
“Sometimes I look back and wonder if my life wouldn’t have been simpler if I hadn’t done it.”