Microwave oven has sparkings on a mug! Last response: February 24, 2010 7:25 PM in Other Consumer Electronics Share niwaz_malik February 23, 2010 8:57:09 PM hi, what causes the sparks on a mc oven, when the mug is made of dried mud? More about : microwave oven sparkings mug thelivingflesh February 23, 2010 9:08:57 PM there must be some linings of gold ribbons on the mug. usually made to keep it intact. they are not aaaaaa.compatible with it. guruofchem February 24, 2010 7:25:19 PM definitely some metal in whatever mud was used to make it - microwaves be not happy with most metals... Can't find your answer ? Ask ! Publish !