The Sultanganj Buddha in detail.

The Sultanganj Buddha is 2.3m high and 1m at its widest point and weighs about 500kgs. It was cast by the technique known as the 'lost wax' process, in which a solid core of clay is overlaid with wax. The sculptor models the fine details in the wax coating. The wax is covered with a liquid layering of clay and plaster which hardens to form a mould. When heat is applied the wax melts and molten metal is poured in. The finished statue is finally obtained by removing the outer casting when cool.

The Sultanganj Buddha is a splendid example of the renowned Gupta sculptural style which itself had been shaped by European and Persian influences that came to India through the trade routes with Rome and West Asia.

The Sultanganj Buddha conveys an image of calm and tranquillity and a spiritual detachment from the material world . The Buddha's sangathi (monastic robe) clings so closely to the body that it is almost invisible, but for a series of string-like folds, giving the figure a wet-looking appearance. The right hand is raised in abhayamudra (a gesture of reassurance or protection) while the left hand, with palm outward and held downwards indicates the granting of a favour.

"The Sultanganj Buddha is a great example," continued Martin. "It's a fantastic object. The first object to ever enter the museum's collections and many people would say it's the single most important object in Birmingham Museum."

"It tells us so much. It tells us this incredible history of ancient art and Buddhism, the story of the building of the Indian Railway system, and the impact of British colonialism. The fact that this amazing piece of sculpture was snatched away and brought to Birmingham, to a museum that wasn't even built at the time.

"It was considered it would be a great starting object for the people of Birmingham to have.

"It's been on show in Birmingham ever since it was acquired in 1864, and been on show in the museum ever since the museum opened in 1885, and so that gives it part of Birmingham's own history."

Some of the items chosen have great monetary value, others have little or none, but all are priceless in how they bring to life moments from history.