Robin egg blue
Robin egg blue, also called eggshell blue or robin's-egg blue, is a shade of cyan, approximating the shade of the eggs laid by the American robin, an abundant songbird of North America. The egg pigment is biliverdin, a product of the breakdown of heme.
The first recorded use of robin egg blue as a color name in English was in 1873, though earlier references in English to colors similar to that of robin's eggs were made as early as 1844. The "robin's egg" glaze appeared during the Yongzheng Emperor’s reign in China, and Yixing potter Hua Fengxiang made works with "robin's egg" glaze.