Polymeric sand is a good sand to use to fill the joints between pavers. This type of sand is used in between concrete pavers, stone pavers and brick pavers. Plain sand can be used to fill between pavers, but polymeric has advantages.
Polymeric sand is a fine sand that is mixed with additives such as silica. The additives create a binding agent that locks together when water is added. Polymer sand improves durability, prevents washouts, deters weeds and is resistant to ants. Polymer sand can usually be found wherever pavers are sold. It can also be found at most local home improvement stores.