I think the answer to this question is that there are very few abstract words for colors in the Tanach altogether. Rather words are used to describe objects or processes that produce certain colors.
There's no word for purple in the abstract, but there is a word for purple dye: ארגמן
There's no word for blue in the abstract, but there is word for sky-colored dye: תכלת
There's no word for green in the abstract, but there is a word for green vegetables: יָר֣וֹק
And even words that had already taken on an abstract meaning in the times of Tanach, the root of word reveals its original source as a description of an object or process. Red is אָדֹם, like blood. White is לבן, to clean.