U.S. Geological Survey circular/U.S. Geological Survey Circular · 1952 · 14 citations · 1 references
Natural SciencesGeologyMine PlanningMine SurveyingMineral Resource EstimationCoal GeologyMining GeologyResource EstimationCoal Basin AnalysisCoal GeographiesCoal HistoryCoal Reserves AssessmentCoal Resource Estimation
2. Anthracite. I. Anthracitic 3. Semianthracite. .. 98 per cent or more V.M., 2 per cent or Dry F.C., 92 per cent or more and less than 98 per cent (Dry V.M., 8 per cent or less and more than 2 per cent) Dry F.C., 86 per cent or more and less than 92 per cent (Dry V.M., 14 per cent or less and more than 8 per cent) Nonagglomeratingb II. Bituminous4 1. Low volatile bituminous coal.... 2. Medium volatile bituminous coal.
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