The article focusses on the comparison of metaphorical expressions related to color in English and Persian, using a model developed by Al-Hasnawi (2007). The linguistic material analyzed in the article includes color-related idioms, metonymic expressions, similes and proverbs, selected on the basis of containing at least a single color-related word. The objectives of the study are to determine the differences in cognitive mappings between English and Persian speakers in relation to color terms, and to explore issues of translation equivalence. The study found most of the metaphors in English and Persian to be dependent on culture, based on different mappings, and thus not readily recognizable in word-for-word translation. Only a minority were similar in terms of the underling mapping. As a result, cognitive equivalence between English and Persian is found to be merely relative.