Brass is a mixture of copper and zinc. This is a traditional south Indian coffee filter from the days of the yore. Fill coffee powder on the top compartment and pour steaming hot water on it. Close the lid and wait for the decoction to trickle down.
Boil milk in a separate vessel. Add sugar and the coffee decoction to the steaming milk to make a perfect cup of south Indian filter coffee.
Clean using a small piece of tamarind and salt. This will remove the blackness in the metal. Then scrub clean with regular dish wash. This gives the brass a golden glow.