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Deerite [Fe_(12)~(2+) Fe_6~(3+) Si_(12)O_(40)(OH)_(10)] was first discovered in the metamorphic magnetite-bearing quartzites which are interlayered with blueschists in Aksu Precambrian blueschist terrane. The deerite-bearing mineral association includes ① deerite+riebeckite+stilpnomelane+ilvaite+magnetite+quartz and ② deerite+stilpnomelane+magnetite +quartz based on the investigation under microscope. The study of mineral chemistry shows that the deerites from Aksu Precambrian blueschist are Mn-poor deerite similar to that from Alps. But the deerite from Aksu is the nearest to the end member of deerite. According to the equilibrium P-T region of deerite determined by Lattard and Breton (1994), the deerites in metamorphic magnetite-bearing quartzites from Aksu Precambrian blueschists were formed under the conditions of pressure lower than 1.0 Gpa, temperature ranging from 300 to 400℃ and about the 10℃/km geothermal gradient. The deerite in metamorphic magnetite-bearing quartzites from Aksu blueschist
Deerite [was first discovered in the metamorphic magnetite-bearing quartzites which are interlayered with blueschists in Aksu [J]; Fe_ (12) ~ (2+) Fe_6 ~ (3+) Si_ (12) O_ (40) Precambrian blueschist terrane. The deerite-bearing mineral association includes ① deerite + riebeckite + stilpnomelane + ilvaite + magnetite + quartz and ② deerite + stilpnomelane + magnetite + quartz based on the investigation under microscope. The study of mineral chemistry that that the deerites from Aksu Precambrian blueschist are Mn-poor deerite similar to that from Alps. But the deerite from Aksu is the nearest to the end member of deerite. According to the equilibrium PT region of deerite determined by Lattard and Breton (1994), the deerites in metamorphic magnetite -bearing quartzites from Aksu Precambrian blueschists were formed under the conditions of pressure lower than 1.0 Gpa, temperature ranging from 300 to 400 ° C and about the 10 ° C / km geothermal gradient. The deerite in metamorphic magnetite-bearing quartzite s from Aksu blueschist