Polymetallic complex iron ore (composite ores) containing valuable metals are smelted in blast furnaces. During this process, the oxides of strategic metals such as titanium (Ti), chromium (Cr), and rare earth (RE), along with impurities like silicon (Si), aluminum (Al), calcium (Ca), and magnesium (Mg), migrate to the slag phase. These composite slags represent a valuable secondary resource, often referred to as “artificial ore,” rather than mere waste. This study introduces the innovative Selective Precipitating and Separating Technology (SPST) to address the challenge of separating valuable components from composite slags. As a case study, the titanium enrichment phase (perovskite) is selectively precipitated and separated using titanium-bearing blast furnace slag. SPST involves a sequence of interrelated processes, including selective enrichment of valuable components, followed by selective precipitation and growth of targeted phases, and concluding with the selective separation of the enriched phases. This work presents a detailed discussion of the theoretical principles underlying the separation of the perovskite phase from slag and provides the results of industrial tests. The titanium concentrate obtained is subsequently processed into high-grade titanium-rich materials suitable for use as feedstock in the production of titanium dioxide.