Rasashastra, the classical Ayurvedic discipline centered on Parada (mercury), documents sophisticated protocols for processing mercury, metals, and minerals to produce therapeutic formulations and to pursue metallic transformation (Lohavada). This paper traces the historical development of Indian iatrochemistry from early Siddha practitioners and Nagarjuna to the medieval codification in Rasaratnakara and related treatises, highlighting key texts, procedures, and philosophical rationales behind mercury‑centred alchemy. It examines the rationale for using mercury—its unique liquid state, amalgamation properties, and perceived proximity to gold in elemental ordering—and summarizes core Rasashastra methodologies such as Samskara purification sequences, Bija‑vedha (seed) transmutation, and apparatus‑based operations described in classical sources. The review juxtaposes textual descriptions with modern scientific perspectives, clarifying that literal proton‑level transmutation is not feasible under conventional chemistry while noting that historical practices anticipated metallurgical techniques, alloying, and surface treatments now amenable to analytical validation. Contemporary scientific opportunities are outlined, including adapting purification principles for nanoparticle synthesis, exploring low‑energy metallurgical processes inspired by traditional methods, and using computational modeling to probe proposed mechanisms. The paper concludes by recommending interdisciplinary research pathways—combining textual scholarship, experimental archaeology, analytical chemistry, and materials science—to responsibly evaluate Rasashastra claims and to translate promising principles into safe, evidence‑based applications in nanomedicine and sustainable metallurgy.