Mica, dry-ground

The coarse mica concentrate is either respiraled to produce a product with a grade suitable for use by wet grinding mica producers, or floated to further upgrade it for specialty high grade dry ground mica products. 

Tables 4 and 5 show properties of ground mica products. For all forms of ground mica the index of refraction is 1.58 wt %, Mohs hardness is 2.5, oil absorption (Brit. Stand. 3483) is 60.75%, water solubihty (Brit. Stand. 1765) is <0.3%, the phericity factor is 0.01, and the softening point in °C is 1538. For Microni2ed and wet ground micas the brightness (green filter), pH, and apparent density in kg/m are 75, 5.2, and 160—224, respectively for dry ground mica, 66—75, 6.2, and 192—561, respectively (1).

Dry ground mica concentrate is processed into usable products hy several dillerent grinding methods. Relatively coarse particle sizes (1.651-0.147 mm (10-100 mesh)) are used in oil-well drilling muds. 

Mica 325, 325FF, 325MF, 325D, AMC, 160 D - dry ground mica for rubber applications. 

Other fillers with significant shares of the world market in plastics are wollastonite (4%) and mica (2%), both chiefly in PP and polyamides. Consumption patterns for mica vary from region to region. Only about 5,000 tonnes of (mainly) dry ground mica was consumed in plastics in the US in 2002, which represents a mere 5% of total US consumption. 

Drikalite, Calcium carbonate, ECC International Drool Disc, Barrel insulation blanket. Unitherm Dry-Ground Mica, Mica, Franklin Industrial Minerals... 

Barwick Standard Distribution Corn. Dry Ground Mica Typical Screen Analysis ... 

Dry-ground mica - Flake mica flotation concentrates are at least partially dried and then ground in mills appropriate for the particle size desired. Coarse-milled products (>100 mesh) are processed with hanuner mills and screens or air separators. Fine-ground products, -100 mesh to -325 mesh in particle size, are processed in fluid energy mills, usually with superheated air. 

Micronized mica - This is dry-ground mica milled to -20 or -10 micrometers in fluid energy mills using superheated steam. Some is calcined for use in cosmetics. 

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