14.3-10. Separation by the sinking and flotation method. A mixture of particles contains quartz, whose relative density is 2.65, and hematite whose density is 5.1. It is desired to separate the particles by a sinking and flotation method, using a suspension of fine ferrosilicon particles, whose density is 6.7. What consistency, in % volume of ferrosilicon solids, must be maintained in the aqueous medium to achieve separation?