Abstract <p>The material composition of placer (alluvial) dolomite-type nephrite from the Tsipa River in the nephrite-bearing region of the Vitim Highland has been examined. Initial data on the mineral composition of both inner and outer zones of the alluvial dolomite-type nephrite pebbles have been obtained. Placer nephrite is characterized by an inherited staining rim, a small amount of accessory minerals, fine-grained texture, randomly fibrous structure, and elevated alkali content. Chemical composition features of the staining rim formed under exogenous conditions include the development of Mn–Fe hydroxides, with a significant increase in the Fe³⁺ content and elevated levels of Co and Ba. A genetic relationship has been established between the placer nephrite and its primary source (nephrite from the Kavokta deposit). Comparison between primary and placer dolomite-type nephrite promoted the identification of diagnostic characteristics for conducting expert assessments.</p>