Why is ancient Egyptian blue considered the world's first synthetic pigment?

The answer

Egyptian blue (calcium copper silicate, CaCuSi₂O₆), created around 2500 BCE, is the earliest known artificially produced pigment. Egyptians manufactured it by heating a mixture of limestone, sand, copper ore, and natron to approximately 900°C. The pigment adorned everything from tomb paintings to the Bust of Nefertiti. In 2009, researchers at the Georgia Institute of Technology discovered that Egyptian blue emits near-infrared radiation when illuminated - a property now exploited in biomedical imaging, telecommunications, and forensic fingerprint detection. The pigment's recipe was lost after the fall of the Roman Empire and wasn't successfully recreated until 1814, when chemists finally analyzed ancient samples to reverse-engineer the formula.