In Tsuyazaki area, Fukuoka Prefecture, there spread Cretaceous granodiorites and Tertiary sediments, in which many kinds of zeolites occur as the veinlets with quartz or calcite and as the cementing materials of conglomerate. These zeolites were identified as heulandite, laumontite, leonhardite, stilbite and analcime by X-ray diffraction, and their chemical compositions were obtained by electron probe micro-analyser. Heulandite has a composition of Ca_{0 65} Na_{4 70} K_{0 74} Mg_{0 08} Al₈₂₅ Si_{28 09} O₇₂ · 22.87H₂O and occurs as the cementing material of conglomerate. Stilbite has a composition of Ca_{1 9} Na_{6 16} K_{0 58} Mg_{0 04} Al_{9 74} Si_{26 03} O₇₂· 27.47H₂O and often occurs on the heulandite crystal. Leonhardite has a composition of Ca_{3 41} K_{0 42} Mg_{0 01} Al_{7 74} Si_{16 38} O₄₈·13.96H₂O and occurs as the veinlets with quartz. Analcime has a composition of Na_{0 94} Ca_{0 03} Al_{0 98} Si_{2 02} O₆ 0.99H₂O and occurs as an idiomorphic crystal in the vug of sandstone in association with a petrified wood. Judging from their occurrences, it is thought that the zeolites found in Tsuyazaki area were formed by the hydrothermal process.

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A mineral, “ferriphlogopite” is characterized by its chemical compo-sition KMg₃ (Fe³⁺Si₃) O₁₀ (OH)₂, in which Fe³⁺ occupies tetrahedral site. The mineral was once called “iron-rich phlogopite” or “tetrafer-riphlogopite”. The chemical composition, Mössbauer parameters, and optical and X-ray properties of “ferriphlogopite”, which is associated with carbonatite from Palabora mine, South Africa, have been described : (K_0.88Na_0.01)_Σ0.89 (Mg_2.76Fe_0.39)_Σ8.15 (Fe³⁺_0.58Al_0.36Si_3.02)_Σ3.96O_9.96 (OH)_1.81 where Fe³⁺>Al; ΔE 2.63, δ1.12 Fe²⁺ in M2, ΔE 0.51 δ0.20 Fe³⁺ in T (mm/s, δ refer to iron metal) ; 2V(-)_??_5⁰, N_x=1.558, N_Y_??_N_Z=1.612-1.615, X=deep brown, Y=Z=pale brown, X>T=Z, The anisotropic charge transfer band in the violet region ; C 2/m, a 5.361 b 9.288 c 10.292 β 100.02° Z=2.

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In order to process the diffraction spots on the two-slits Weissenberg photograph (Mito et al. 1981), two computer programs have been pre-pared. One program is for construction of a chart by drawing the axial reciprocal lattice lines. The chart is available for interpretation of the general-inclination Weissenberg photographs taken on a camera with any diameter and any translation constant. The failure in indexing of high Bragg angle reflections can be prevented by using the chart. The other program is for refinement of the lattice constants and the orientation angles of crystallographic axes to the rotation axis. The reflections are indexed from the initial values of unit cell parameters, camera parameters and crystal orientation parameters. The parameters are optimized by the nonlinear least-squares method. The determination of crystal orientation parameters allows us to dispense with the procedure of the crystal alignment on the goniometer. These programs have been employed for the synthetic diamond crystals of the spineltype twin to refine the cell dimensions and obliquity angle.

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