The colour depends on the properties of the semiconductor, and these can be tuned to produce light that is similar to natural daylight but with virtually no ultraviolet or heat.

The best way to see the correct colour of your aura is in a daylight against a white wall. I know that some people use black background but I did not try this.

Dark as it was getting, I could still see these changes, though but as mere alternations of light and shade; for colour had faded with the daylight.