Abstract:Pyroxmangite was discovered for the lirst time during the study of Wujiateng section of the Bajiazi lead-zinc pyrite deposit in Laioning Province. Occurring commonly in lead-zinc pyrite orebodies and near-ore skarn, it is associated with spessartine, pyrite and alabandite. Being reddish brown in color and short rismatic in form, it has two sets of cleavages and refractivities of Ng 1 .749~1 .753, Np 1.737~1.748, Nm 1.734~1.741,(+)2 V 430 and Do3.786~3.792. Chemical composition of the pyroxmangite depends largely on Mn and Fe,which cause remarkable variation of its color. The mineral formula for this mineral is Ca0.27~0.43Mg0.43~0.57)0.57~1.00(Mn4.94~5.77Fe0.36~1.36)6.16~6.37[Si6.86~7O21].The mineral falls into the anorthic system and can be divided into two sorts of colors with different X-ray powder diffraction patterns. The reddish brown mineral has X-ray spectral lines of 3.133 (1 00),2.958(34),2.503(7),2.183(15)and 1.919(26)while the rose red mineral shows 3.133(100),2.960(42),2.502(13),2.183(18) and 1.919(45).Both sorts of pyroxman- gite have such cell parameters as a= 6.690~6. 697A, b=7.573~7.592A,。C=17.41~17 .40A, a =113.84;~113.88A β=82.35A~82.30A and;γ=94.64; ~94.74;Its formation is related to the contact replacement between igneous rocks and Mn-containing dolomite, and the Pb, Zn and S mineralization is so closely connected with the origin of pyroxman}ite as to have ore-hunting significance.