This paper describes the finding of staurolite-bearing gneiss from the Higo metamorphic terrane and proposes new mineral zones in the Kosa area, Kumamoto Prefecture. Previous mineral zones of the Higo metamorphic terrane proposed by Obata et al. (1994) consist of five zones: Zone A characterized by Chl + Ms, Zone B by Bt + Ms + And, Zone C by Kfs + Sil + Bt, Zone D by Grt + Crd + Bt, and Zone E by Opx in metapelites. They identified three zones from B to D in the Kosa area. However, we found that sillimanite appears together with Grt + Crd, hence this paper shows that Zone C is absent in the Kosa area. New finding of Opx in the southern-most part of the area made it possible to define three mineral zones; Bt zone, Grt-Crd zone, and Opx zone, in the order of increasing grade from north to south in the Kosa area. Analysis of staurolite-bearing assemblage in a KFMASH system together with textural evidence reveals that the following reactions occurred in the staurolite-bearing gneiss in the excess of Kfs, Qtz and H₂O:
[Sil] Str + Bt = Grt + Crd
[Bt] Str = Grt + Crd + Sil
    Chemographic analysis of these reactions together with Grt-Bt geothermometers shows the metamorphic condition of P = 200 MPa and T = 600-620°C, which is much lower in pressure than that estimated by Osanai et al. (1996) in the Toyono area, about 10 km west of Kosa.

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Ramsbeckite was found as a vein forming mineral in altered shale at the Hirao mine, Minoo, Osaka, Japan. It occurred as aggregates of euhedral granular crystals up to 0.5 mm across, in association with sphalerite, chalcopyrite, smithsonite, aurichalcite, amorphous manganese dioxide, schulenbergite, brochantite, serpierite, limonite and an unidentified mineral. It was emerald green to blue-green in color with a vitreous luster in hand specimen. An EPMA and CHNS/O analyzer gave the empirical formula (Cu_9.380Zn_5.542Ni_0.034Co_0.027Fe_0.020Mn_0.013)_Σ15.016[(SO₄)_3.871(CO₃)_0.166]_Σ4.037(OH)_21.958·6.06H₂O on the basis of O = 44. The unit cell parameters were a = 16.106 (3), b = 15.568 (2), c = 7.109 (1) Å, β = 90.23 (1)°, and Z = 2. The mineral was optically biaxial negative with refractive indices α = 1.676, β = 1.704 and γ = 1.707, and 2V_X(calc) = 37.8°. The Vickers microhardness was 162 (144-182) kg/mm² (10 g load), and the Mohs hardness was 3.5. The measured density was 3.36 g/cm³. It is likely that ramsbeckite at the Hirao mine crystallized from Cu and Zn-bearing fluids.

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The Hirao Limestone located in northeast Kyushu is bordered on the north by unmetamorphosed Paleozoic strata (the Kagumeyoshi Formation), and on the south by the Tagawa metamorphic rocks, a member of the Sangun Metamorphic Rocks. They are thermally metamorphosed due to the Cretaceous Hirao granodiorite intrusion. As a result, neither the fossil record nor the record of the regional (Sangun) metamorphism has been preserved. We investigated the geologic relationships among these units. The tectonic collage model associated with accretionary processes proposed by Kanmera and Nishi (1983) seems the most reasonable. The Hirao Limestone and the uppermost part of the Tagawa metamorphic rocks may be a large olistolith formed during the accretion of the Palaeozoic formation.
    Petrological studies show that the area was thermally metamorphosed as revealed by widespread occurrences of biotite in pelitic rocks both in the Tagawa metamorphic rocks and in the Kagumeyoshi Formation. Garnet occurrences in the pelitic schists close to the Hirao granodiorite suggest about 700°C for the peak metamorphic temperature of contact metamorphism, based on garnet-biotite geothermometers. The high temperature condition is consistent with the occurrence of corundum in quartz-free layers of the pelitic schist, and that of anthophyllite in quartz-free layers of the basic schists consisting of hornblende + plagioclase. These lines of evidence are indicative of the amphibolite facies condition of contact metamorphism.

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Baddeleyite, zirconolite and calzirtite were found in lateritic rocks from Ryoke and Chichibu Terranes in southwestern Japan. This is a new type of natural occurrence of the minerals. The lateritic rocks are associated with limestone widely distributed into Ryoke metamorphic and Chichibu non-metamorphic complexes. Baddeleyite, zirconolite and calzirtite are associated with Ti minerals such as anatase, ilmenite, perovskite and titanite. Calzirtite occurs simultaneously with perovskite. Rhabdophane-(Ce) like minerals also occurs in the lateritic rocks such as in emeries from Ko-Oge Island. Baddeleyite and calzirtite have compositions close to the ideal compositions, ZrO₂ and Ca₂Zr₅Ti₂O₁₆. Zirconolite, CaZrTi₂O₇, accommodates significant amounts of Fe, Nb, Ta, and small amounts of Al and REE. Minor amounts of ACT are also found in the mineral. The chemical substitution in zirconolite is controlled by the reaction: REE³⁺ + 2(Al + Fe)³⁺ + (Nb + Ta)⁵⁺ ⇔ Ca²⁺ + 3Ti⁴⁺. Baddeleyite is a relict of the lateritization stage, or formed by the decomposition of zircon. Zirconolite formed during the prograde stage of metamorphism by the reaction; calcite + 2anatase + baddeleyite ⇔ zirconolite + CO₂. The formation of calzirtite in Ca-metasomatic emery is independent from the deformation of zirconolite during the prograde stage of metamorphism.

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