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40th Birthday Gifts for Women, Fabulous 40 Limited Edition, 14oz Gold Pattern Coffee Mug, Microwave Dishwasher Safe, Unique Gift for Mom, Best Friend, Wife, Sister, Coworker, Beautifully Gift Boxed. : Amazon.co.uk: Home
![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?width=640&crop=smart&auto=webp&s=78cf0b4e014d28417e156ba1ef725fd743a98b87)
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
![patmoseal Coffee Mug Ceramic for Office & Home, Large Capacity 19oz Coffee Cup Porcelain for Tea & Milk, Microwave & Dishwasher Safe (Lake Green) : Amazon.co.uk: Home & Kitchen patmoseal Coffee Mug Ceramic for Office & Home, Large Capacity 19oz Coffee Cup Porcelain for Tea & Milk, Microwave & Dishwasher Safe (Lake Green) : Amazon.co.uk: Home & Kitchen](https://m.media-amazon.com/images/I/61febe1i5KL._AC_SX425_.jpg)
patmoseal Coffee Mug Ceramic for Office & Home, Large Capacity 19oz Coffee Cup Porcelain for Tea & Milk, Microwave & Dishwasher Safe (Lake Green) : Amazon.co.uk: Home & Kitchen
![UNIVERSAL TRAVELLER - Reusable coffee cup with lid and heat sleeve. 16 oz ceramic travel mug. Portable to go coffee mug. Microwave safe & dishwasher safe. Unique Pink Glaze : Amazon.co.uk: Home UNIVERSAL TRAVELLER - Reusable coffee cup with lid and heat sleeve. 16 oz ceramic travel mug. Portable to go coffee mug. Microwave safe & dishwasher safe. Unique Pink Glaze : Amazon.co.uk: Home](https://m.media-amazon.com/images/I/91nu7d5mhkL._AC_SL1500_.jpg)