Gypsum Quality

qualityMinus 6 inch gypsum rock
Minimum purity 93%
Maximum chlorides 70 PPM
Maximum humidity at loading port 2%

Minus 2 inch gypsum rock 
Minimum purity 93%
Maximum chlorides 70 PPM
Maximum humidity at loading port 2%

Minus 1/2 inch gypsum rock
Minimum purity 91%
Maximum chlorides 70 PPM
Maximum humidity at loading port 2%

Sampling and analysis procedures

Sampling is done several times at different stages. First the core holes are analyzed each meter, then the blasting holes are analyzed each meter again. Also we sample the gypsum after blasting. We then sample the conveyor of the primary crusher, secondary crusher and the conveyors in the stockpile.

During the loading of a vessel, we take samples avery 500-1000 tons loaded.

On each sample taken we analyze, purity and chlorides. On the samples taken on the conveyor belts, we also get a sizing analysis.

To analyze the gypsum rock Caopas follows the ASTM C-471 procedure.