Rapid growth in transportation infrastructure in the country demands for large quantities of aggregates to be available for pavement construction. Due to the scarcity of natural aggregates, cost-effective waste resources are now being used in pavement subbase and base courses. This study is focused on producing artificial aggregates using two types of industrial wastes—overburden (OB) mine waste and fly ash—that are generated in large quantities worldwide. Fly ash is a by-product of coal combustion, while overburden mine waste is generated during the extraction of minerals from the earth’s crust. Typically, these wastes are disposed of in landfills, posing significant environmental risks. The present study is aimed at producing artificial aggregates using two methods involving (a) crushing or breakage of casted specimens, and (b) pelletization technique. In both methods, a liquid alkali activator (LAA), comprising a combination of sodium hydroxide and sodium silicate, is utilized as a binding agent. Results indicate that pelletized aggregates have superior impact resistance (34%) and lower water absorption (10%) than crushed aggregates from casted specimen (44% impact resistance and 14.6% water absorption). Modifying NaOH concentration or incorporating water repellent chemicals like trichloro silane presents an avenue for future research to address and limit high water absorption of these aggregates. It is concluded that pelletized aggregates can complement natural aggregates in flexible pavement construction.