Ninety-one-year-old May Barrie threw back a glass of stout to celebrate winning the $60,000 Balnaves Foundation Sculpture Prize at the Sculpture by the Sea judging at Bondi yesterday.

Her hefty, 3m-high sculpture made of Moruya granite was among the more dignified entries in a 500-strong field tending towards the kitsch factor.

The prize is the biggest she has won in 60 years of sculpting.

"I know it's a good work and now I'm glad that other people agree," Barrie said.

"I'm surprised and pleased to have been given this award - I hope I'm not just dreaming this!"

Barrie created the work in 1996, but according to her daughter Tori De Mestre, the artist continues with the often physically demanding tasks required of stone sculptors. She is known to retreat to the traditional arsenal of grinders, cutters and polishing tools several mornings a week.

"She feels she's got lots of things she still wants to do and say," Ms De Mestre said.

The sculpture, titled time and tide (granite monolith II), was a reference to the ancient proverb "time and tide waits for no man", and was intended as a comment on the forces of nature and time marching on.

Founding director of Sculpture by the Sea, David Handley, said its subtlety set it apart from other entries.

"It's worked so well by May with her carving and her polishing of the sculpture - the parts that she decides to polish, the parts that she decides to keep rough, the parts that she decides to carve, and those bits that she chooses to leave as they were," he said.

"Who would have thought May Barrie has been hidden from us for so long?"

Barrie has lived at the Calderwood property Callemondah since 1950.

She was born in Western Australia and in her life has travelled all over the world, including Afghanistan, Turkey, Greece, Italy, India, Nepal, Uzbekistan, Morocco, Oman, Mongolia, Tunisia and Thailand.

Sculpture By the Sea is the world's largest annual free-to-the-public outdoor sculpture exhibition. It runs until November 15.