Constable-Maxwell Cage Cup

Pictured above, it is the most expensive piece of glass ever sold, having brought £2.6 million at Bonham's in 2004.

"Once part of the British Rail Pension Fund ancient glass collection, the third century A.D. bowl was made according to the cage-cutting technique where blank, mould-cast glass is cooled and then laboriously carved into a lattice design," wrote Rachel Spence of this singular piece in the January 5, 2006 Financial Times "How To Spend It" magazine.

The 8" x 10" cup is believed to have once been a lamp.