Australia's richest person, mining magnate Gina Rinehart, has bought Glencoe Station in NSW for her Wagyu beef operation in a deal worth $30 million.

The 10,000-hectare property north of Dubbo is less than 20 kilometres from her $25 million purchase last year of one of the world's largest Wagyu cattle herds and two properties, Boogadah and Kagan, from businessman Paul Salteri.

Rumours of Mrs Rinehart's purchase of Glencoe from former Meat and Livestock Corporation chairman and mining businessman Dick Austen began to swirl last week when the property's Hartley Grazing Company listed 1000 angus cows for sale.

Mrs Rinehart's agricultural ambitions have spread as far north as the Kimberley region with her purchase of the Fossil Downs cattle station in a deal worth about $30 million.

Glencoe Station was bought in an off-market deal negotiated by Colliers International's Richard Royle and Logical Livestock's Simon McKittrick.

Mr Royle confirmed a sale but refused to comment on the price or buyer.