A powdered incense clock made of brass, copper and paktong. Paktong translates as 'white copper' and is a silver-white alloy consisting of copper, zinc and nickel. The clock is shaped in the form of a ruyi-sceptre, and consists of an assemblage of two trays, an incense seal, a tamper plate and a cover. The pieces fit inside each other. The first tray or base is to store powdered incense. The second tray is to hold a fine layer of white wood ash as a bed for the incense. The incense seal is laid down on top of a bed of wood ash, while the incense powder is being poured over it. Then the incense powder is compacted lightly by a tamper plate, which is placed on top to produce a continuous trail of powdered incense. The progress of the burning incense helps tell the time. Finally, the incense clock is covered by a pierced copper plate to prevent any breeze that would accelerate the burning and alter the steady measure of time.
This type of item was once used for time keeping, but was later used by monks or scholars in meditation and for aesthetical pleasure.