Colour

Marble is usually a light coloured rock. When it is formed from a limestone with very few impurities, it will be white in colour. Marble that contains impurities such as clay minerals, iron oxides or bituminous material can be bluish, gray, pink, yellow or black in colour. (Geology.com).

At the Emporium, you can see for yourself all the multitudes of colour even within the same egg.