Foschiy N. Geological and economic evaluation of petrified wood in south-eastern part of Ukraine.

The dissertation presents the geological and economic characteristics of petrified wood from south-eastern part of Ukraine. It has been determined the correlation between the decorative properties, mineralogical composition and value of petrified wood. Criteria for this kind of gem quality evaluation are formulated. The quality factors of petrified wood evaluation on the basis of polishing degree has been developed and varieties have been identified. First identified four varieties of petrified wood in the degree of polishing, fracture and size of the samples. The criteria for petrified wood evaluation were given, which are based on the technology of manufacturing products. Geological and economic indicators of petrified wood production have been identified on the example of Zaliman area. Processing technologies have been specified, the costs of raw materials and final products have been calculated.