Source: Midrash Rabah, BaMidbar, b; 7. Some of the tribal colors depicted below may be inaccurate due to a misunderstanding of the text. In addition other opinions are found in different sources.
The Midrash says that each Tribe had its own color over which was depicted the Tribal Symbol.
For details see: Tribal Characteristics in a Nutshell
For a related issue, see: Tribal Colors
Note we have given Dan below an orange-amber type color though elsewhere he is allocated a shade of blue.
We have given Asher a sea-blue type color. This is in accordance with what seems to be the majority opinion of the Rabbinical Commentators.
For another opinion with variant Tribal colors to the ones above see: