Inspired by the titles of Krees & Van Leeuwen, Colour as a semiotic mode: notes for a grammar of colour (2002), and Bernez, Grammaire des couleurs (2014), I pose the question whether it is possible to talk about a real grammar of colours, i.e. an analysis of the chromatic vocabulary in a morphosyntactic, semantic and pragmatic perspective. How do the individual colour names fit in the traditional classification of the different parts of speech? Are they considered to be nouns or adjectives? How are they declined? Are colour adjectives gradable (Kleiber, 2007)? Do we find particular derivation paradigms (rosso-arrossire, giallo-ingiallire)? Where are attributive colour adjectives located in the noun phrase (la bianca neve vs. la Casa Bianca)? Recent chromatology studies have shown that the colour designations are particularly suitable for the study of idioms in an interlinguistic and intercultural perspective (Ronga et al., 2014; Bazzanella, Ronga & Strudsholm, 2016). In fact, the primary colours of the iris are often used with figurative meanings (e.g. rosso and nero in the language of politics and finance). I propose to discuss these questions in an Italian-Danish comparative perspective basing my analysis on electronic corpora.