The Cyclosizer is a laboratory precision apparatus for the rapid and accurate determination of particle size distribution within the sub-sieve range.Particles are separated according to their Stokesian settling characteristics by a principle based on the well known hydraulic cyclone principle. The effective separating range is 50 to 8 microns for material of a specific gravity similar to quartz (SG 2.7), but the lower limit may extend down to 4 microns for particles of high specific gravity (for example - Galena with its SG of 7.5). Samples of up to 100 grams of minus 200 mesh or minus 325 mesh material may be separated into five fractions. The time required for an effective separation can range from 10 minutes to as long as 30 minutes. Extra time is required for dewatering and drying and weighing the separate fractions.The apparatus consists of five 3 inch diameter cyclones and ancillary equipment all mounted on a console cabinet with all necessary controls and gauges. The unit is shipped completely assembled and ready for use. It required as service items, single phase power, clean water at 9 to 14 liters per minute and a floor drainage point.