Orin Hargraves at the Visual Thesaurus:
Once you step away from the main compass points of the color wheel, however, English gets more interesting, and more grabby. English speakers came into contact fairly early on with names of pigments and dyes through trade and cultural exchange and these words, mostly of foreign origin, have been kicking around in English for many centuries. Perhaps even more so than the principal colors, they have retained their power to evoke specific and vivid images: consider, as a sample, alizarin, bistre, cochineal, henna, indigo, lapis lazuli, ocher, saffron, sepia, umber, vermilion. Add to these the partly-overlapping list of color names with a real-world referent (whether natural or manufactured) such as amber, burgundy, chartreuse, ebony, fuchsia, ivory, lilac, olive, turquoise — all of which are also mainly foreigners with long-time, permanent resident status in English.
From the rich vocabulary available you might get the impression that English speakers are connoisseurs of color, but usage statistics tell a different story.