This Heath Ceramics Stacking Coffee Mugs 4 piece set in black is a vintage mid-century modern style made in California. These ceramic mugs feature a matte finish and are stackable. The interior glaze is a beautiful rose pink. The Heath brand is known for its artistic designs in pottery. These original mugs bear an impressed backstamp . See photos. Perfect for adding a touch of retro charm to your kitchen or dining area, these Heath ceramics are a must-have for collectors of unique and stylish pottery.