Introduction

This chapter introduces the reader to the world of aggregates. Data on the worldwide consumption of aggregates are discussed as well as their main types and sources, including recycled aggregates. Aggregate applications are described and the mining cycle of aggregate production is briefly introduced. The importance of the influence of aggregate production in the circular economy is further discussed, including sustainability, and the criticality of aggregate resources is highlighted. Finally, illegal extraction of aggregates is cited as one of the most important environmental concerns of aggregate production.