Abstract:Kleemanite, a rare phosphate mineral, was found in the Baokeng manganese oxide deposit, Guangdong, in 1983. It has the same mineralogical characteristics as kleemanite from the Iron Knob deposit in Australia. Its chemical composition is ZnO 20.79%,P2O5 34.76%,Fe0 0.67%,A1203 24.38 % (by EPMA) and H20 19.79% (by DTA and TGA),giving a chemical formula of Zn1.02 (Al1.90 Feo.04) (P04)1.95 (OH)2.01.3.14 H20. Its crystals are pale yellow in color and transparent D=2.84 H=3. Average refractive index 1.606. Stronger lines in X-ray diffraction pattern are 4.76(10),9.095 (8),3.638(6), 3.333(6),3.313(6),3.095(6),4.91(5),4.733(5),3.977(5),3.134(5),2.857(5)。 Calculated unit cell parameters: ao=7.274A,bo=7.185A,c0=9.788A,β=110.244° and Z=2, being of monoclinic system. Space group:P2, P21, P2/m or P21/m. Infrared spectra show absozption bands at 3600, 3510, 3430, 3160, 1163, 1130, 1040, 592, 530 and 490(cm-1),and differential thermal analysis demons- trated endothermal peaks at 235, 311 and 651(℃).