Mugs have feet to raise the bottom off the surface.
Ikea Ungdom Black & White Stripes and Dots Mugs 3H Retired Set of 4
Coffee Mugs, Tea Cups, & Coasters - IKEA
Libbey Austin 17.5-ounce Large Porcelain Coffee Mug, Set Of 4, Basalt Blue : Target
Why Your IKEA Mug Has A Little Chip At The Bottom - Ikea Mugs
Temp-tations Set of (2) 16-oz Mugs with Spoons
Mug Double Walled Glass - PLENTY Mercantile & Event Venue
Why Your IKEA Mug Has A Little Chip At The Bottom - Ikea Mugs
Why Your IKEA Mug Has A Little Chip At The Bottom - Ikea Mugs
Ikea Mug Photos and Images & Pictures
Why is there a chip at the bottom of most coffee mugs? - Quora
AskTamara: Which mugs are Lead-free? How can I tell if my mug has unsafe levels of Lead? Which mugs do you use?
Why do IKEA mugs have a strange chip on the bottom? - Quora