The first synthetic pigment – Egyptian Blue – was made by the Egyptians around 4500 years ago. A technique developed by scientists at the British Museum has allowed them to discover traces of Egyptian blue on ancient objects that no longer have their original paint finishes intact. Before the Egyptians learned how to make a synthetic blue pigment from sand and copper the main blue pigment was obtained from the mineral lapis lazuli, first found in Afghanistan about 4500 BC. Extracting blue from lapis lazuli was extremely expensive.

Blue remained an expensive pigment however and came to symbolise truth, peace, virtue and authority in fine art. Images of Mary usually showed her wearing a blue robe. Blue was used for symbolic reasons. Cheaper blue pigments became widely available in the modern era of synthetic pigments.

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