What I saw was sorta off white, but many 4aco/ho-xxx chems have sort of a gray color as the degrade. This doesn't seem to affect potency.
The sample I'm looking at is sort of brownish white, like brown sugar but lighter. For some reason I had a funny feeling that the sample was mislabeled.
When I got a batch of older 2c-3, it was brownish-white. New batch that I got later was pretty much pure white, had a texture like flakes of soap. Be careful with older stuff, it can break down into nasty compounds. That older batch had the same effects as the newer batch, but it gave me a massive headache, worst of my life. Next day I felt terrible. So if you decide to use it, use a small amount to test it first.
Degrade is perhaps the wrong word, oxidation is more accurate. This doesn't hurt potency, but makes dosing a bitch. Most 4-trypts today are the fumerate salt, which seems to avoid the problem altogether.
Good advice with any RC, particularly if your source carries DOX chems. 20mgs of mislabeled DOI would ruin your whole weekend.