Procedure-Transfer approximately 1 g of the sample prepared to pass a 100-mesh (149-um) U.S. standard sieve to a tare-weighed porcelain or platinum crucible. Cover with a lid and weigh accurately to within 0.1 mg. When testing quick- lime, the crucible cover is not required. Also, quicklime may be placed directly into a muffle at 1000°C avoiding preignition. Pre-ignite in a muffle furnace at approximately 400°C for 30 min. Then increase muffle temperature to 1000°C t 20°C, and maintain at this temperature for a minimum of 20 min or until t mass is obtained. The difference between the original of the sample and the final mass represents the loss on ignition.