Physics of mixing different powders

[JoAuSc]

Let's say you have two powders (say, flour and brown sugar) which are to a certain degree mixed with each other. Is there a commonly accepted parameter that determines how well mixed this mixture is? Obviously there's a difference between having the mixture so unmixed that you can see a line dividing one powder from the other, and having the mixed so well mixed it's a shade of light brown rather than brown and white, but I don't know how I'd determine that quantitatively.

 

[KingNothing]

To my knowledge, there is no standardized way of measuring how well mixed two powders are.

However, there are many ways of measuring it this, how do you think it could be measured?