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A great number of tremendous glaucous crystals were found in middle-upper oxidization of HongshanCu-Au deposit, Kalatage district, eastern Tianslian, NW-China. The authors made systematic analysis such as XRD, TA and identified it is a rare kind of sulfate-Paracoquimbite [Fe-2 (SO4)(3) center dot 9H(2)O]. Paracoquimbite of Hongshan deposit was reported for the second in the world (first case reported at 1935 in Chile). And the Paracoquimbite megacryst ( d = 8cm similar to 12cm) of Hongshan deposit are much bigger and more rare than that ( d = 1. 95cm) of Chuquicamata porphyry copper deposit, in Northern Chile. Paracoquinibite occurs with its polytype coquimbite. The chemical analysis results of Paracoquimbite ( wt%) are: SO, 42, 55, Fe2O3, 28. 19, H2O 28. 72, CaO 0. 02, MgO 0. 01, Al2O3 0. 03, Na2O 0.02, total 99. 54; and its characteristic data of XRD analysis are: 4. 61 (100), 8. 89 (83), 3. 38 (67). The chemical analysis results of Coquimbite ( wt%) are: SO3 42. 31, Fe2O3 28. 61, H2O 28.98, MgO 0.01, Al2O3 0.01, total 99. 92; and its characteristic data of XRD analysis are: 8. 27 (100), 5. 46 (76), 2. 77 (76). The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mossbauer spectrum analysis. Their thermal reaction and facies change mechanism were also explained. Systemetic EPMA analysis shows that At impurity in crystal lattice, disfigurement of crystal are important to polytype formation of paracoquimbite and coquimbite besides stack fault. The oxidization zone ties on the upper part with a depth of 50km similar to 60m. It is composed of natural elements, chlorides, Fe-oxide and sulfates with various colors, in which sulfate minerals dominated. Besides paracoquimbite, five minerals were founded in China for first time. Now these sulfate minerals have been used as a new type of acid-resource for copper smelting. So the Paracoquimbite megacrysts may be practicality and collection value.