Arlene Wagner displays best of her 7,000 nutcrackers at Tsuen Wan Plaza

When people ask Arlene Wagner how she came to collect 7,000 nutcrackers from around the world, she replies: "I guess we were just nuts!"

Nutcrackers, because of their highly practical use, their whimsical designs and intricate craftsmanship, chronicle the history of the Western world, and captured Wagner's imagination.

"There's no other tool that is made in as many designs or as many materials as the nutcracker," said the 87-year-old, who started collecting the items with her late husband in the 1970s.

"I was a dance teacher and taught The Nutcracker ballet, which was how we started [collecting nutcrackers]," said Wagner, who would use nutcrackers in her productions. "Then we just wanted to share them and let people enjoy them, and the history and stories they tell us."

Now 75 items from her collection - including an intricately carved wooden tool from 17th century France, a contemporary model made in the form of Yoda from Star Wars, and a construction worker nutcracker with a piece of the Berlin Wall at its feet made in 1990 - are on display at the Tsuen Wan Plaza in Tsuen Wan until January 1 next year.

What began as a hobby soon became a passion, as Wagner and her space scientist husband made more than 35 trips to Europe to scour antique shops and nutcracker-makers for gems.

Eventually, their collection was too big to display at home. In 1993, the couple bought a building in Leavenworth, in the US state of Washington - a tourist town and their home - and set up The Nutcracker Museum, which opened its doors to public in 1995.

Currently, 6,000 of their nutcrackers are on display at the museum in the United States, and the oldest one - a metal lever nutcracker from the Roman Empire - has been dated to between 200BC to 200AD. The oldest nutcracker in the world was found in Italy and made in around 500BC, said Wagner.

Her collection comes from more than 50 countries, but mainly from Germany, France, England and the US.

Nutcrackers were once a daily household item - used for preparing the food that was a vital source of protein. But they also became a creative outlet, with delicate and intricate craftsmanship put into their making.