A property investor just signed one of the deals of the decade in Mayfair

Cain Hoy Enterprises, a property investor, just signed one of the biggest property deals in the history of London's most exclusive area.

The US-based company has bought 19 South Audley Street in Mayfair for an undisclosed amount.

While the amount the building sold for wasn't disclosed, Cain Hoy did say that it is one of the five biggest deals to happen in Mayfair in the last decade, and Property Week reports that the sale was worth around £80 million.

South Audley Street is around 48,000 square feet, pretty much the exact size of an American Football field.

It was first built in 1845, but rebuilt to designs by architect Ernest George, who designed Southwark Bridge.

The building is probably best known as being the home of Thomas Goode, an upmarket shop that sells china, glasses, and silver. In the past, Queen Victoria, and multiple Russian tsars also bought their crockery from Goodes.

Cain Hoy has a history of making big investments in London. Last year it put a substantial amount of money behind the new Stage development in Shoreditch, east London, and, in conjunction with Sager Partners, secured a loan to build Islington Square in north London. Overall, Cain Hoy says it has invested more than £1 billion ($1.4 billion) since it was started in 2014.

Mayfair, one of London's most exclusive areas, isn't exactly short of massive property sales. Last week, Business Insider reported that super wealthy Qatari investors have bought more than £1 billion worth of property in the area, including a £200 million house once described by the Queen as making "Buckingham Palace look rather dull."