Mineralogical and biological witnesses of Redikar burial of the 10th-11th centuries

The study of products of copper alloys of the Lomatov culture of the X-XI centuries from the collection of the Cherdyn Museum revealed two types of patina. The first pseudomorphic might be composed of intergrowths of chlorides formed upon interaction with the sweat of the hands, or a zonal rim of cuprite-malachite-azurite composition, due to interaction with groundwater. The second type, which distorts the shape of the original product, is associated with the leaching of copper and other metals and the crystallization of oxides and salts on the surface in the form of worm-like, kidney-shaped and drusoid aggregates. Fragments of mineralized biological objects (wings, eggs and larvae of flies, mole hair) found on the surface of the patina testify to the rapid oxidation of bronze, which is associated with flooding of the soil of the burial ground immediately after burial.