שמות כו, יד : וְעָשִיתָ מִכְסֶה לָאֹהֶל עֹרֹת אֵּילִם מְאָדָמִים וּמִכְסֵּה עֹרֹת תְחָשִ ים מִלְמָעְלָה:The Baal haTurim points out that the gematria of תחש (with one for the word is 609) which equals שש גונים. Thus the Tachash prides itself with its colors (like Unkelus) - or it means six colors (like the Medrash) that the skin this animal actually contained six colors. The beautiful colors where used to adorn the top of the Mishkan.