![I feel like this is a good one. I put this ceramic mug in the microwave sometimes and overtime this black sludge appears in the outside? What is it and why do I feel like this is a good one. I put this ceramic mug in the microwave sometimes and overtime this black sludge appears in the outside? What is it and why do](https://preview.redd.it/omkr9m7r1ld01.jpg?auto=webp&s=5b4fab7ea6f97c9b65983ebbbb4038008faa7ac2)
I feel like this is a good one. I put this ceramic mug in the microwave sometimes and overtime this black sludge appears in the outside? What is it and why do
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Amazon.com | Sistema Microwave Soup Mug with Lid and Steam Release Vent, Dishwasher Safe, 22.1-Ounce, Red: Klip It: Coffee Cups & Mugs
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Camco Life is Better at the Campsite Speckled Mug | Microwave and Dishwasher Safe | Ceramic, Red (53235) - Walmart.com
![Amazon.com | Home-X - Microwave Soup Mug Set with Secure Snap Close Vented Lids, 22 oz Mugs Allow You to Heat and Eat Soups, Noodles, Hot Cereal and More in a Single Amazon.com | Home-X - Microwave Soup Mug Set with Secure Snap Close Vented Lids, 22 oz Mugs Allow You to Heat and Eat Soups, Noodles, Hot Cereal and More in a Single](https://m.media-amazon.com/images/I/611YK8Bbx-L._AC_UF894,1000_QL80_.jpg)
Amazon.com | Home-X - Microwave Soup Mug Set with Secure Snap Close Vented Lids, 22 oz Mugs Allow You to Heat and Eat Soups, Noodles, Hot Cereal and More in a Single
![The Risks Of Heating A Stainless Steel Coffee Mug In The Microwave: Tips For Safe And Efficient Heating – TheCommonsCafe The Risks Of Heating A Stainless Steel Coffee Mug In The Microwave: Tips For Safe And Efficient Heating – TheCommonsCafe](https://cdn.thecommonscafe.com/can_stainless_steel_coffee_mug_go_in_microwave.jpg)