[CliffordK (OP)]

Ok,
This should be easy enough to do at home.

Say you have a container full of nuts, some large ones like Brazil Nuts, and a few smaller ones like filberts, pistachios, or almonds.  Shake up the container, and which ones come to the top, and which fall to the bottom?

You can actually do a similar experiment with various materials as long as the density of the different materials in the mix is about the same, balls, sand&gravel, etc.

When you eat a container of salted nuts, why do you often find salt and small pieces of the nuts left at the bottom?