Expanded clay aggregates are formed by heating natural clay at 1200 degrees Celsius temperature. This results in developing honeycombed structures interconnected withing clay balls. The clay balls are generally rounded in shape. These are extremely lightweight and strong. Clay balls do not change the pH of the soil.

Benefits :

Extremely lightweight co friendly chemicals used to increase soil porosity does not alter soil can prevent root reduce watering requirements prevent soil evaporation if used for top dressing

Usage:

Clay balls are good potting medium and can be used along with soil, best for top dressing
Just mix in potting mix and it will show its benefits
Use it as a potting medium for growing especially cactus and succulent plants among others
Clay balls are also used to fill the pot base to increase water drainageClay balls can also be used to fill the base of self-watering pots

It is not the source of nutrients but can hold on nutrients, moisture, and increase aeration in the soil.