nAstatkiA thick liquid residuum obtained in the distillation of Russian petroleum, much used as fuel.
Century Dictionary and Cyclopedia
nastatkiThe residuum from the distillation of Russian petroleum after the more volatile hydrocarbons, up to and including kerosene or illuminating oil, have been driven off. It occurs in the proportion of 10 to 15 per cent., and has a specific gravity of .9 to .95. This material is to some extent treated for the production of lubricating oil, but is for the most part utilized as fuel.