Biomineralisation processes invariably occur in the presence of multiple organic additives, which act in combination to give exceptional control over structures and properties. However, few synthetic studies have investigated the cooperative effects of soluble additives. This work addresses this challenge and focuses on the combined effects of amino acids and coloured dye molecules. The experiments demonstrate that strongly coloured calcite crystals only form in the presence of Brilliant Blue R (BBR) and four of the seventeen soluble amino acids, as compared with almost colourless crystals using the dye alone. The active amino acids are identified as those which themselves effectively occlude in calcite, suggesting a mechanism where they can act as chaperones for individual molecules or even aggregates of dyes molecules. These results provide new insight into crystal–additive interactions and suggest a novel strategy for generating materials with target properties. Färbeprozesse: Eine bemerkenswerte Kontrolle über Kristallisationsprozesse kann durch den Einsatz von Kombinationen löslicher Additive erreicht werden. Für Kombinationen von Aminosäuren mit Farbstoffmolekülen wird gezeigt, dass bestimmte Aminosäuren die effiziente Okklusion des Farbstoffs bewirken können, was zu stark gefärbten Einkristallen führt. Farblose Kristalle bilden sich in Abwesenheit der Aminosäuren.