This study investigates the effectiveness of amine-coated nanobubbles (NBs) in the flotation of coarse quartz at a laboratory scale. Experiments were performed in a flotation column at a pH of 10.5, utilizing a mixture of bubbles of varying sizes: macrobubbles (D32 = 1200 µm) and amine-coated NBs (D32 = 180–220 nm). Flotation recoveries were assessed for quartz particle sizes ranging from 150 µm to 1000 µm and with varying amine concentrations (mg amine/g quartz). The findings demonstrated over 90% recovery across all particle size ranges when the numerical concentration of amine-coated NBs reached at least 7 × 10¹⁰ NBs per gram of quartz, achieved with 1.5 mg of amine per gram of quartz. The NBs adhered rapidly to the surfaces of the quartz particles, promoting the attachment of the larger bubbles. This interaction resulted in the formation of light, hydrophobic, and highly buoyant aggregates (“clusters”) of coarser particles, which ascended swiftly to the surface of the column. The effect of amine-coated NBs was further validated in a mechanical cell using a real iron ore sample. The results demonstrated the significant potential of this innovative technique for recovering difficult-to-treat minerals in flotation systems, particularly those containing coarse quartz and silicate particles.