Rare Earth Elements (REEs) are substitutional elements found in rock-forming minerals and are regarded as critical materials in the energy transition supply chain. The exploration of REE potential aims to identify prospective zones by examining both megascopic and microscopic characteristics of rocks, along with their elemental composition, to support the development of priority commodities. This research was conducted in the Adian Koting District, North Tapanuli. Rock samples were collected from outcrop sites and analyzed using petrographic methods (thin and polished sections), along with geochemical testing through X-Ray Fluorescence (XRF) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Samples were prepared as polished sections for microscopy and ground to 200 mesh for geochemical analysis. Megascopically, the rocks are classified as coherent igneous rocks—specifically, plutonic granite types. They exhibit colors ranging from light gray to white with black specks; brownish-white with reddish-brown patches and black spots; and creamy to grayish-white. Texturally, the rocks show equigranular, hypidiomorphic-granular, and phaneritic textures. The grains are subhedral with a massive structure, composed mainly of quartz, plagioclase, biotite, opaque minerals, and hornblende. Microscopically, REE-bearing minerals such as zircon, monazite, and xenotime are present. Monazite occurs in prismatic, platy, or elongated crystal forms, often large and twinned. Monazite and xenotime are commonly associated and found as inclusions in biotite or quartz, suggesting early crystallization. Zircon appears as small, bright-colored inclusions. XRF analysis reveals the presence of cerium (Ce) and lanthanum (La), with Ce concentrations ranging from 74.3 to 97.5 ppm and La from 90.2 to 141.0 ppm. ICP-MS results show dominant REE elements including Sc (3.5–5.5%), La (4.1–5.6%), Y (4–6.1%), Ce (3.5–4.8%), Gd (3.9–5.8%), Tm (5.4–5.6%), and Eu (3.1–5.1%). Minor REE elements include Dy (1.9–3.6%), Yb (0.8–3.5%), and Er (0.473–84.4%). These findings indicate that the Adian Koting area holds significant potential as a natural resource for industrial technology materials.