Melbourne artist Warren Lane has won the $7500 Bald Archy first prize with The Banquet of Gina and Ginia, a painting that depicts the mining billionaire eating chocolate cake as her favoured daughter looks on.

A portrait of Australia's richest person was always likely to win the satirical portrait prize on numbers alone. The mining magnate was the most popular subject, featuring in eight entries.

Lane, who painted a rolled-up copy of The Age newspaper in the artwork - a reference to Rinehart's purchase of Fairfax Media shares - modelled the portrait on 17th century Dutch painter Jan Victors' The Banquet of Esther and Ahasuerus.

In the original painting, the Jewish heroine Esther alerts her husband, the Persian King, of a plot against his empire.