In the "soil and sand" bottle, which type of soil is on the bottom?

Sand will remain at the bottom as its made up of rocks.

Explanation:

As sand is apart of the soil and soil is made up f liquids gases and solids and sand are natural that comprises of the 85% of the particles.  And soil has decomposed parts of plants and animals and has clay, mud and thus is darker in color and sand is light in color.

There is totally sun all the way down there.