(under the class definition) Methods and apparatus applied to particular materials or articles in which the invention lies in the application of the separation, which may or may not be novel, per se, to such particular substances or articles.
(1) Note. Search should be made in the appropriate classes which deal with the extraction, manufacture, or preparation of the particular substance or articles.
SEE OR SEARCH CLASS
23, Chemistry: Physical Processes,
293+, for processes of preparing or treating inorganic compounds and nonmetallic elements by physical action.
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing, appropriate subclasses for apparatus for preparing or treating inorganic compounds and nonmetallic elements by physical action.
423, Chemistry of Inorganic Compounds, 1+, for extraction of inorganic materials.
