Afwillite and jennite occur as fissure-filling veins up to 3 mm wide in the spurrite zone in skarns at Fuka. Jennite occurs also as alteration products of spurrite. The occurrences suggest that afwillite was formed from fluids in fractured spurrite and that jennite was formed by alteration of afwillite and by hydration decomposition of spurrite.
Afwillite crystals are tabular up to 0.3 mm in width or radial aggregates of fibers up to 4 mm in length. The mineral is white in color with a vitreous luster and colorless in thin section. The mineral is monoclinic with unit cell parameters of a=16.276(4), b=5.6336(4), c=13.236(3)Å and β=134.89(1)°. EPMA and wet chemical analyses gave an empirical formula Ca_2.98(Si_2.00B_0.04) _Σ2.04O_4.06 {(OH)_5.90F_0.04} _Σ5.94 based on O+OH+F=10. Optically, the mineral is biaxial positive with refractive indices α=1.617, β=1.621 and γ=1.632, 2V=56°, and elongation positive or negative. Vickers microhardness is 351∼383 kg/mm² (25g load) and density is 2.63g/cm³.
Jennite in the vein occurs as parallel or radial aggregates of acicular crystals with length up to 0.2 mm. The mineral is white in color with a vitreous luster and colorless in thin section. The mineral is triclinic with unit cell parameters of a=10.577(4), b=7.271(5), c=10.828(4)Å, α=99.60(4), β=97.62(3) and γ=110.18(4)°. EPMA and wet chemical analyses gave an empirical formula Ca_9.00H_2.00(Si_5.95Al_0.02) _Σ5.97O_17.93(OH)_8.00·6.07H₂O based on O=32. Optically, the mineral is biaxial negative with refractive indices α=1.548, β=1.562 and γ=1.570, and elongation positive. Vickers microhardness is 145∼155 kg/mm² (25g load) and density is 2.33 g/cm³.

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The conductivities of synthetic Ag₃AsS₃ and Ag₃AsSe₃ have been measured as a function of temperature and frequency by the complex impedance method. Their impedance plots exhibited the characteristic semicircles which were attributed to ionic conduction behaviors in the bulk and the grain boundary. The transport number of charge carrying species in Ag₃AsS₃ was determined by the Tubandt method. The electronic contribution to the total conductivity of Ag₃AsS₃ was negligible small at room temperature; less than 1%. The logσT versus 1/T plot of Ag₃AsS₃ had a kink of the slope near about 375 K. The activation energies below and above 375 K are evaluated as 0.23 and 0.35 eV, respectively. Ag₃AsSe₃, measured only below about 330 K, gave an activation energy of 0.24 eV. The magnitude of the conductivity of Ag₃AsSe₃ is almost ten times larger than that of Ag₃AsS₃ below 375 K. The conductivities of Ag₃AsS₃, 1.5×10⁻³ S/cm at 427 K, and of Ag₃AsSe₃, 1.6×10⁻³ S/cm at 331 K, are sufficient magnitudes as superionic conductors.

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Coloradoite was found in one of polished sections from the Daté mine, southwestern Hokkaido by means of physical properties and an electron microprobe analysis.
On the basis of the assemblage of coloradoite and the associated minerals, the fugacity ranges of Te₂ and S₂ are estimated at from 10^−7.9 to 10^−10.9 atm and from 10^−10.1 to 10^−11.4 atm, respectively, in hydrothermal solution, as the formation temperature of coloradoite can be assumed about 300°C.

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A structural study of the metamict zircon “naegite” has been carried out by obtaining radial distribution function (RDF) from measured X-ray scattering intensity data. Structural parameters of interatomic distances and coordination numbers were estimated from the RDF data using the pair function method. The silicon atom was found to occupy a tetrahedral site of oxygen. The structural parameters of first neighbouring Zr–O pair agree well with those of crystalline zircon, although the slight decrease in its interatomic distance is detected. Since the correlation of the cation-cation pairs around 0.30 and 0.36nm are well attributed to those of the crystalline zircon, the metamict zircon is considered to have similar short range order as that found in the structure of crystalline zircon.

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