Love drinking tea, but find stains in your favourite china mug or cup. SIMPLE SOLUTION.
Make a paste of Bicarbonate soda (carb soda)
1/4 to 1/2 a teaspoon of soda and same of water in your cup
Simply rub with a soft cloth or sponge.
Rinse (reapply and continue if necessary)
Wash in a mild detergent.
This technique also works on glass, corningware and enamel products..