Group 12 element zinc and cadmium which makes geological separation unlikely. As a consequence, cadmium is produced mainly as a byproduct from mining, smelting, and refining sulfidic ores of zinc, and, to a lesser degree, lead and copper. One place where metallic cadmium can be found is the Vilyuy River basin in Siberia. Although mercury is an extremely rare element in the Earth's crust, because it does not blend geochemically with those elements that constitute the majority of the crustal mass, mercury ores can be highly concentrated considering the element's abundance in ordinary rock. The richest mercury ores contain up to 2.5% mercury
Average variance extracted Average variance extracted In statistics (classical test theory), average variance extracted (AVE) is a measure of the amount of variance that is captured by a construct in relation to the amount of variance due to measurement error. The average variance extracted was first proposed by Fornell & Larcker (1981). The average variance extracted can be calculated as follows: Here, formula_2 is the number of items, formula_3 the factor loading of item formula_4 and formula_5 the variance of the error of item formula_4. The average variance extracted has often been used to assess discriminant validity based on the following "rule of