By basing on the same physical model and treatment method, as used in our recent works [1, 2, 3, 4, 5], we will investigate the critical impurity densities in the metal-insulator transition (MIT), obtained in three n(p)-type degenerate [GaAs1−xTex,GaAs1−xTex,GaAs1−xTex]- crystalline alloys, 0≤x≤1, being due to the effects of the size of donor (acceptor) d(a)-radius, rd(a), the x-Ge concentration, and finally the high d(a)-density, N, assuming that all the impurities are ionized even at T=0 K. In such n(p)-type degenerate crystalline alloys, we will determine:(i)-the critical impurity densities NCDn(CDp)(rd(a),x) in the MIT, as that given in Eq. (10), by using an empirical Mott parameter