Reverse　anionic　flotation　of　carbonate-containing　iron　ores　is　quite　a　challenging　process.　Studies　on　this　ores　conducted　in　many　laboratories　or　beneficiation　plants　have　obtained　poor　concentrate　grades　and　separation　between　quartz　and　iron　minerals,　even　when　valuable　minerals　are　adequately　liberated.　The　presence　of　carbonate　minerals,　such　as　siderite,　causes　a　detrimental　effect　on　quartz　flotation　recovery　(froth　product)　and　separation　selectivity　between　quartz　and　iron　minerals.　In　this　work,　the　effect　of　carbonate　minerals　on　quartz　flotation　from　iron　mineral　was　investigated　using　sodium　oleate　as　collector,　starch　and　calcium　as　regulators.　Microflotation,　adsorption,　PHREEQC　calculation,　and　Fourier　transform　infrared　spectroscopy　(FTIR)　measurements　were　conducted　in　the　investigation.　Carbonate　minerals　(i.e.,　siderite　and　dolomite)　adversely　affected　the　floatability　of　quartz　and　separation　between　quartz　and　hematite.　Starch　dosage　experiment　results　clearly　showed　that　the　reduction　of　quartz　recovery　in　the　presence　of　carbonate　minerals　was　mainly　related　to　starch.　In　addition,　mineral　dissolution　and　sodium　carbonate　dosage　experiments　evidently　exhibited　that　CO32-　dissolved　species　of　carbonate　minerals　passively　affected　quartz　flotation　recovery.　By　contrast,　both　starch　and　CO32-　dissolved　species　of　carbonate　minerals　adversely　affected　the　flotation　recovery.　FTIR　showed　that　the　strong　drop-off　in　quartz　recovery　in　the　presence　of　carbonate　minerals　was　due　to　the　adsorption　of　CaCO3　precipitations　on　quartz　surfaces　and　further　their　interaction　with　starch　molecules.　The　appearance　of　CaCO3　precipitations　was　caused　by　reaction　of　Ca2+　from　the　hydrolysis　of　CaCl2　and　CO32-　dissolved　species　of　carbonate　minerals.　To　decrease　the　passive　effect,　a　potential　strategy　to　improve　the　flotation　performance　of　iron　ores　that　contain　carbonate　minerals　at　strong　alkaline　pH　is　suggested　to　remove　carbonate　minerals　before　separation　between　hematite　and　quartz.　(C)　2016　Elsevier　B.V.　All　rights　reserved.