The conductivity and blue color originate from boron impurity. Their numbers are controlled by the concentrations of impurity elements, i.e. doping concentration. These naturally occurring ores typically included arsenic as a common impurity. The Coulombic forces will deflect an electron or hole approaching the ionized impurity. Kalash theology has very strong notions of purity and impurity. Monohydrate pTSA contains crystalline water as well as water as Impurity. These naturally-occurring ores typically included arsenic as a common impurity. He detected it as an impurity in yttrium oxide, YO. All natural sphalerites contain concentrations of various impurity elements. This is known as "ionized impurity scattering". The castes, states David Gamble, were associated with ideas of relative purity/impurity. The remaining impurity consists of urea. Others work by chemically or physically removing or sequestering the impurity. This cleaning removed a substance that generated the required impurity. Copper, an impurity in molybdenite, is less soluble in ammonia.