opinion: SCHLABACH COAL COMPANY, Petitioner, v. NATIONAL LABOR RELATIONS BOARD, Respondent.
  No. 77-1610.
  United States Court of Appeals, Sixth Circuit.
  Dec. 14, 1979.
  Milan E. Frase, Frase & Weir, Coshocton, Ohio, for petitioner.
  Elliott Moore, Deputy Associate Gen. Counsel, N.L.R.B., Washington, D.C., Bernard Levin, Director, Region 8, N.L.R.B., Cleveland, Ohio, for respondent.
  Before CELEBREZZE and KEITH, Circuit Judges, and PHILLIPS, Senior Circuit Judge.
  Howard E. Perlstein, Barbara G. Gehring, Washington, D.C.
  ORDER
  This case is before us on petition for review and cross-petition for enforcement of an order of the National Labor Relations Board. The decision of the Board is reported at 231 NLRB No. 154.
  The Schlabach Coal Company is a sole proprietorship which operated several small coal mines in the vicinity of Baltic and Cambridge, Ohio. The Board found that the company tired to avert the unionization of its employees by the United Mine Workers Union by fostering a rival union, the Christian Labor Association, in a Board-supervised election.
  Specifically, the Board found that the company violated the act by assisting the Christian Labor Association, by threatening to go out of business if the United Mine Workers rather than the Christian Labor Association won the election, and by threatening to discharge United Mine Workers Union supporters. In addition, the Board found that the company violated the act by firing employee Larry Mills because of his activities on behalf of the United Mine Workers.
  The record overwhelmingly supports the Board’s findings. Company supervisors and foremen made no secret of their preference for the Christian Labor Association. They openly stated that Mr. Schlabach would shut down if the United Mine Workers won. Further, there is substantial evidence that the supervisors and foremen threatened to fire anyone who voted for or supported the United Mine Workers and carried out that threat by firing Larry Mills.
  The company asserts that the shutdown statements were merely truthful responses to employee questions. This claim is precluded by NLRB v. Gissel Packing Co., 395 U.S. 575, 618-19, 89 S.Ct. 1918, 23 L.Ed.2d 547 (1969). The company also claims that Mr. Mills was fired for a number of valid reasons. Suffice it to say that the record supports the Board’s conclusion that the reasons given were pretextual.
  The Board’s order is enforced.
instruction: What follows is an opinion from a United States Court of Appeals.
  Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
  When coding the detailed nature of participants, use your personal knowledge about the participants, if you are completely confident of the accuracy of your knowledge, even if the specific information is not in the opinion. For example, if "IBM" is listed as the appellant it could be classified as "clearly national or international in scope" even if the opinion did not indicate the scope of the business. 
  
  Your task concerns the first listed appellant. The nature of this litigant falls into the category "private business (including criminal enterprises)", specifically "mining". Your task is to determine what subcategory of business best describes this litigant.
choices: oil and gas coal metals other  unclear