Lime

Weigh empty crucible lid. Record the weight. Tare.

Weigh some limestone into crucible lid. Record the weight.

Put crucible lid into furnace at Cone 05.

Weigh crucible lid after heating and subtract weight of empty crucible lid.

Divide weight of lime by weight of limestone: (after heating)/(before heating).

Compare to theoretical weight of 56%.

Product should taste bitter to pH test paper.