Mass production of cast-iron garden decoration proliferated with the advent of the industrial revolution, around the middle of the 19th century, when manufacturing techniques and the rise of the middle class meant that garden statuary could be made cheaply for a wide and avid audience anxious to purchase it.

"You would have gone to the 19th-century equivalent of a garden center and bought an urn," says Spencer Swaffer, an English antiquarian who carries a large inventory of antique cast-iron urns in his shop in Arundel, south of London. Compared to stone -- the primary material used up to that point -- cast iron was more durable and easier on the pocketbook. "Stone cracked and shattered in frost and even in strong sunlight; it also commanded higher prices," he says.

Which is not to say that the new material was completely impervious to the elements. The metal, especially when exposed to the outdoors, as garden pieces would be, invariably weathers. The pieces were also usually painted repeatedly, and after a hundred years, paint peels and chips. But it is precisely that kind of weathering and aging that attracts aficionados today.

"There is nothing more beautiful to me than an old, rusty piece of garden decoration with layers and layers of peeling paint on it," says Birmingham dealer Robert Hill, whose impressive collection includes the pieces pictured here.

For designers, that timeworn quality is a selling point, and it can be used to great effect indoors. A garden urn used as a centerpiece or in a foyer is an insouciant touch. "They mix with the most formal furniture, making it less grand," says Swaffer. "And they can dress up a more humble piece of painted furniture."

The effect is successful outdoors as well. Paul Fields, director of design at Lambert Landscape in Dallas, finds a delicacy in cast iron that he can't get from stone. "It gives a garden a sense of an English interior, with that layered look that goes back centuries," he says. "I think of New Orleans gardens, with that lacy ironwork."