Price Variance. Definition: Price variance is the actual unit cost of a purchased item, minus its standard cost, multiplied by the quantity of actual units purchased. The price variance formula is: (Actual cost incurred-standard cost) x Actual quantity of units purchased. = Price variance. If the actual cost incurred is lower than the standard cost, this is considered a favorable price variance.
Calcium carbonate is a common, naturally occurring calcium salt that is often used as a source of calcium in supplements. Its abundance in nature makes calcium carbonate the least expensive supplemental calcium salt. It is also a major component of some types of stone that are used in architecture and sculpture.
The calcite form of calcium carbonate forms in all types of rock, according to the Minerals-N-More site. Often, some of the calcium component is replaced by small amounts of Iron, magnesium or manganese. It is found in marble, limestone, sandstone and shale.Calcite is frequently phosphorescent in nature.rand X Pictures/Brand X Pictures/Getty Images. Calcite is a mineral that occurs in the natural geological processes of the Earth. Calcite is a form of calcium carbonate, a type of calcium salt oxide with three atoms of oxygen bonded to one atom of calcium.