Heulandites newly described from Chichijima, the Ogasawara Islands are characterized by higher Si and monovalent cation contents and by higher refractive indices and larger 2V_z as compared with ordinary heulandite, and therefore have intermediate properties between ordinary heulandite and clinoptilolite.
They are divided into two groups based on chemical composition and thermal behavior. According to the classification of Alietti, one group is regarded as heulandite type 1 and the other as heulandite type 2. The latter has higher Si content and more thermally stable framework structure than the former.
The zeolitization to form heulandite is inferred to take place as a result of the devitrification of vitreous host rocks by the actions of deuteric solution and/or the later hydrothermal solution.

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Suzukiite, Ba₂V⁴⁺₂[O₂|Si₄O₁₂], orthorhombic, Amam or Amam2, a=7.089(2), b=15.261(2), c=5.364(1)Å, Z=2, is a new mineral corresponding to the barium analogue of haradaite, Sr₂V⁴⁺₂[O₂|Si₄O₁₂].
The electron microprobe analysis gave : BaO 38.38, SrO 3.21, VO₂ 23.56, TiO₂ 0.20, SiO₂ 33.59, total 98.94%, yielding the empirical formula (Ba_1.78Sr_0.22) _Σ2.00(V⁴⁺_2.02Ti_0.02)_Σ2.04Si_3.97O₁₄ on the basis of O=14.
It is bright green in colour with a vitreous lustre and pale green streak. Cleavages {010}, perfect; {100} and {001}, distinct. Specific gravity 4.0(obs.), density 4.03g/cm³(calc), H. (Mohs) 4 to 4¹/₂ on {010}. It is optically biaxial negative, 2V about 90°, r<v, very strong. Refractive indices: α=1.730(5), β=1.739(calc), γ=1.748(5). Optical orientation and axial colours: a=X=pale green, b=Y=light yellowish green, c=Z= bluish green.
Suzukiite is found in massive rhodonite-rhodochrosite ore from the bedded manganese ore deposit of the Mogurazawa mine, Kiryu City, Gumma Prefecture, Japan, in association with quartz, barite, nagashimalite and a barian roscoelite.

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Fission track annealing experiments under optimized sets of etching conditions have been carried out on biotite mineral from a pegmatitic intrusive body of Pokharia mica mine in Hazaribagh district of Bihar (India). The mean values of range for induced ²³⁵U fission fragments, uranium content and activation energy determined are 19.3±1.6μ m, 0.2ppm, and 1.5eV respectively. The graphs depicting the variation of optimum etch time, activation energy, and track length shrinkage with annealing in track density have been drawn for their use in fission track dating. Annealing characteristics of micaceous minerals like biotite, chlorite, vermiculite, phlogopite and muscovite show that the track clock in them got reset at 100, 110, 125, 150 and 170°C respectively between the annealing eras 10⁵ to 10⁷ years. The analysis of track annealing in biotite and its comparison with other micaceous as well as nonmicaceous minerals suggest that biotite is lowest geological thermometer among the minerals studied so far in fission track geochronology.

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CuL X-ray emission spectra of copper sulfides were measured by using EPMA. Each wavelength of CuLα line of CuS and Cu₂S is similar to that of Cu₂O. Accordingly, the oxidation state of Cu seems to be univalent in both sulfides.

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