This agate model of a mortar was made in Cambay (Khambat) in Western India in the 19th century and was originally acquired by the Indian Museum in London before being transferred to this museum in 1879. It appears to be a reasonably accurate model of the type of mortar used in siege warfare from the 17th to mid 19th centuries. However, the metal rods on each corner of the carriage are intended to be axles, complete with holes for pins to secure the wheels in place. In reality such mortars were never fitted with wheels and the rods themselves are far too thin to have functioned as such.
The barrel of European mortars of this design were usually fixed at a 45 degree angle (different trajectories being achieved by altering the size of powder charge used). This model is on adjustable trunnions like a conventional cannon which is a feature on some Indian designs. However it lacks any form of elevating device to hold the barrel in position for firing such as a capstan elevating screw or even the simplest method employing wedge shaped chocks. Taken together these features suggest that this was intended to be a toy, rather than an accurate model.