Scanning electron micrographs show the textural differences in representative tripoli rocks from the three major tripoli-producing districts in the United States. Arkansas tripoli preserves the polygonal, triple-point texture of the parent metamorphic novaculite. Illinois tripoli is fine-grained quartz presumably in crystals as deposited from solution. Missouri-Oklahoma tripoli is characterized as friable, porous aggregates of quartz crystals residual after leaching of the parent rock. Each textural type serves preferential uses and applications to which the individual texture is best adapted.