These garden burners are hand-worked from sheets of 2mm Mild/Carbon steel. The level of carbon introduced to this alloy, (approximately 0.2%), has been carefully balanced to provide durability, whilst ensuring it remains sufficiently malleable to achieve our distinctive bowl shape. The steel will continue to rust as soon as it is exposed to the elements. The striking patina this creates will continue to develop over many months, so we do not recommend that these burners are placed on surfaces that are liable to stain as run-off may occur. These burners will provide years of service.