A 25-tonne boulder that crashed into a home in the Christchurch earthquake has raised $NZ60,000 ($44,000) in an online charity auction.

"Rocky" the giant rock smashed through the walls of Phil Johnson's hillside home in the February 22 tremor, coming to rest in his hallway.

Mr Johnson put the boulder up for sale on the Trade Me auction website, attracting more than 300,000 hits and turning his unwanted house guest into an online celebrity.

"For sale, 1 owner, 25-30 tonne landscape feature (answers to the name Rocky)," read his listing for the auction, which ended on Monday.

"He is in pristine condition (just a little bit of concrete dust). Suitable for garden feature, or as in our case, a magnificent addition to your living area... Rocky will enhance your 'indoor-outdoor' flow considerably."

The winning bidder, a New Zealand ski company, paid $NZ50,000 for Rocky. Chief executive James Coddington says the firm plans to display the boulder at its Mount Hutt ski resort.

With Mr Johnson donating all proceeds from the sale to a relief fund for quake victims, the second-highest bidder said she would still pay $NZ10,000 because it was going to a good cause.

The auction generated hundreds of comments, which Mr Johnson says he plans to publish in a book as a way of raising further funds for victims of the disaster, which is believed to have killed more than 200 people.

"Look, I'm in the market for such a rock, but I'm concerned about how house-trained your one is. Clearly it's been digging holes in your back yard. Has it had recent obedience training?" posted one potential buyer, georges21.

- AFP