The new REE-rich, monoclinic, epidote-supergroup minerals ferriakasakaite-(La) and ferriandrosite-(La), found in tephroite Ô calcite veinlets cutting the stratiform ferromanganese deposit from the Shobu area, Ise City, Mie Prefecture, Japan, were studied using electron microprobe analysis and single-crystal X-ray diffraction methods. Ferriakasakaite-(La), ideally A1 Ca A2 La M1 Fe 3+M2 Al M3 Mn 2+ (SiO 4 )(Si 2 O 7 )O(OH) (Z = 2, space group P2 1 /m), has a new combination of dominant cations at A1(Ca) and M3(Mn 2+ ), which are the key sites to determine a root name for epidote-supergroup minerals. The unit-cell parameters are a = 8.8733 (2), b = 5.7415(1), c = 10.0805(3) Å , b = 113.845(2)º and V = 469.73(2) Å 3 . According to the structural refinement (R 1 = 3.13%), the determined structural formula is A1 (Ca 0.54 Mn 2+ 0.46 ) A 2 [(La 0.48 Ce 0.20 Pr 0.07 Nd 0.18 Gd 0.02 ) S 0.95 Ca 0.05 ] M 1 (Fe 3+ 0.42 V 3+ 0.34 Al 0.18 Ti 4+ 0.06 ) M 2 (Al 0.96 Fe 3+ 0.04 ) M 3 ( M n 2 + 0 . 5 0 F e 2 + 0 . 4 3 M g 0 . 0 7 ) ( S i O 4 ) ( S i 2 O 7 ) O ( O H ) . F e r r i a n d r o s i t e -( L a ) , i d e a l l y A1 Mn 2+A2 La M1 Fe 3+M2 Al M3 Mn 2+ (SiO 4 )(Si 2 O 7 )O(OH) (Z = 2, space group P2 1 /m), is the M1 Fe 3+ analogue of androsite. The unit-cell parameters are a = 8.8779(1), b = 5.73995(1), c = 10.0875(2) Å , b = 113.899(1)º and V = 469.97(2) Å 3 , and the structural formula is A1 (Mn 2+ 0.56 Ca 0.44 ) A2 [(La 0.49 Ce 0.20 Pr 0.08 Nd 0.19 Gd 0.02 ) S0.97 Ca 0.03 ] M1 (Fe 3+ 0.40 V 3+ 0.28 Al 0.20 Fe 2+ 0.05 Ti 4+ 0.07 ) M2 (Al 0.97 Fe 3+ 0.03 ) M3 (Mn 2+ 0.50 Fe 2+ 0.40 Mg 0.10 )(SiO 4 )(Si 2 O 7 )O(OH) (R 1 = 2.93%).The two new minerals, which are compositionally very similar overall, are distinguished by occupancy of A1, Ca vs. Mn 2+ . The structural properties of these minerals depend not only on the REE content at A2, but also on the Mn content at A1.

The new mineral, vanadoallanite-(La), found in the stratiform ferromanganese deposit from the Shobu area, Ise City, Mie Prefecture, Japan, was studied using electron microprobe analysis and single-crystal X-ray diffraction methods. Vanadoallanite-(La) is a rare-earth element-rich monoclinic epidote-supergroup mineral with simplified formula CaLaV3+AlFe2+(SiO4)(Si2O7)O(OH) (Z = 2, space group P21/m) characterized by predominantly V3+ at one of three octahedral sites, M1. The crystal studied shows large V (∼8.4 V2O3 wt.%), Fe (∼13.8 Fe2O3 wt.%; Fe2+/total Fe = 0.58) and Mn (∼8.8 MnO wt.%) contents. A small amount of Ti is also present (∼1.3 TiO2 wt.%). Structural refinement converged to R1 = 2.96%. The unit-cell parameters are a = 8.8985(2), b = 5.7650(1), c = 10.1185(2) Å, β = 114.120(1)° and V = 473.76(2) Å3. The cation distributions determined at A1,A2 and M3 are Ca0.61Mn0.39, (La0.46Ce0.14Pr0.07Nd0.18)Σ0.85Ca0.15 and Fe2+0.56Mn2+0.30Mg0.06V3+0.05Fe3+0.03, respectively. On the other hand, depending on Ti assignment, two different schemes of the cation distribution at M1 and M2 can be considered: (1) M1(V3+0.58Fe3+0.34Ti4+0.08) M2(Al0.92Fe3+0.08), and (2) M1(V3+0.58Fe3+0.42)M2(Al0.92Ti4+0.08). In both cases, the dominant cations at A1, A2, M1, M2 and M3 are Ca, La, V3+, Al and Fe2+ , respectively. According to ionic radius, Ti4+ possibly prefers M2 rather than Fe3+. A large Mn2+ content at A1 also characterizes our vanadoallanite-(La). The structural change of Mn2+-rich allanite-group minerals is considered to be controlled by two main factors. One is the large Mn2+ content at A1 in vanadoallanite-(La), which modifies the topology of the A1O9 polyhedron. The other is the expansion of M3O6 and M1O6 octahedra caused by large octahedral cations, such as Fe2+ and Mn2+, at M3 and the trivalent transition elements, V3+ and Fe3+, at M1.

Two new members of the atacamite family were discovered recently in the Sadamisaki Peninsula, Ehime Prefecture, Japan. Iyoite, MnCuCl(OH)3, is an Mn-Cu ordered analogue of botallackite, while misakiite, Cu3Mn(OH)6Cl2, is an Mn-rich analogueof kapellasite. Both minerals occur in manganese ore crevices in close association with one another. Iyoite forms radial and dendritic aggregates consisting of pale green, bladed crystals. Misakiite commonly exists in emerald green, tabular, hexagonal crystals. The densities of iyoite andmisakiite were calculated to be 3.22 and 3.42 g cm–3 based on their empirical formulae and powder X-ray diffraction data. Under the same axial setting of botallackite, iyoite is monoclinic, space group P21/m, a = 5.717(2), b = 6.586(2), c= 5.623(3) Å, β = 88.45(3)° and V = 211.63(15) Å3. Misakiite is trigonal, space group P3m1, with a = 6.4156(4), c = 5.7026(5) Å and V = 203.27(3) Å3. The structures of both mineralsare classified as layer type and the two are closely related. These new minerals were formed by the reaction between seawater and naturally-occurring manganese ores including native copper. These minerals are challenging to produce synthetically. Misakiite was synthesized successfully usinga hydrothermal method, while iyoite could not be made.

Iseite, Mn 2 Mo 3 O 8 , a new mineral that is a Mn -dominant analogue of kamiokite, is found in the stratiform ferromanganese deposit, Shobu area, Ise City, Mie Prefecture, Japan. It is the first mineral species that includes both Mn and Mo as essential constituents. Iseite is iron -black in color and has a submetallic luster. It occurs as aggregates up to about 1 mm in size made of minute crystals (<20 μm). Iseite has a zoned structure closely associated with undetermined Mn -Fe -Mo oxide minerals with hexagonal forms, and it occasionally coexists with small amounts of powellite. Its Mohs hardness is 4 -5, and its calculated density is 5.85 g/cm , and Z = 2. The Rietveld refinement using synchrotron radiation (λ = 0.413 Å) powder XRD data converges to R wp = 3.11%, and confirms two independent Mn sites-tetrahedral and octahedral-in the crystal structure of iseite, indicating the structure formula Mn