Oreconcentrator . Download PDF Info Publiion number US551826A. US551826A US551826DA US551826A US 551826 A US551826 A US 551826A US 551826D A US551826D A US 551826DA US 551826 A US551826 A US 551826A Authority US United States Prior art keywords pan ore reciproing opening compartments Prior art date Legal status (The legal status is an assumption and .