Inhibitors include dichromates, lime, zinc sulfate, cyanide, water glass, sodium sulfide, and cellulose I. Dichromates can form a thin, insoluble, hydrophilic lead chromate film on the surface of galena, making them a good inhibitor for galena. Lime is a good inhibitor for pyrite. Zinc sulfate, used in combination with sodium sulfide and other agents, can inhibit sphalerite. Sodium sulfide is an inhibitor for sulfide minerals, such as galena and quartz. Cyanide can inhibit sphalerite, pyrite, and copper minerals. Water glass has a strong inhibitory effect on silicate and aluminosilicate minerals, such as beryl, spodumene, feldspar, and mica. Cellulose I is an effective inhibitor for carbonaceous alkaline gangue and chlorite slimes.