Mangani-pargasite, ideally NaCa2(Mg4Mn3+)(Si6Al2)O22(OH)2, is a new mineral species of the calcium amphibole subgroup of the amphibole supergroup. The type specimen was found on the mine dump of the Långban Fe-Mn-(Ba-As-Pb-Sb) deposit in Värmland, Sweden. Crystal chemical analyses resulted in the empirical chemical formula: A(Na0.90Pb0.07K0.03)?1.00 B(Ca1.93Mn2+ 0.07)?2.00 C(Mg4.25Mn3+ 0.39Al0.26 Fe3+ 0.10)?5.00 T(Si6.35Al1.65)?8.00O22 W(OH)2. In order to complete the description of this newly approved (IMA 2018-151) mineral we report here additional data to those published in papers by Jonsson and Hålenius (2010) and Hålenius and Bosi (2012). Mangani-pargasite is biaxial positive, with a=1.635(5), b=1.645(5), g=1.660(5) and the measured optic angle 2V is 85(5)°. The dispersion is weak (r>v), and the optic orientation is: Y||b; Z^c=25(3)°. Mangani-pargasite is red to brownish red with weak pleochroism; X=pale reddish brown, Y=pale reddish brown and Z=pale brownish red; X?Y>Z. The unit-cell parameters are a=9.9448(5), b=18.0171(9), c=5.2829(3) Å, b=105.445(3)°, V=912.39(9) Å3, Z=2, space group C2/m. The ten strongest reflections in the X-ray powder diffraction pattern [d-values in Å, I, (h k l)] are: 8.420, 29, (110); 3.368, 17, (131), 3.279, 49, (240); 3.141, 100, (310); 2.817, 44, (33 0); 2.698, 21, (151); 2.389, 18, (350); 1.904, 29, (510); 1.650, 22, (461) and 1.448, 46, (661).

An inclusive study of tourmaline, a well-known petrogenetic indicator, allowed the reconstruction of late-stage evolution of B-bearing Variscan granodioritic magmas in Sardinia batholith (Italy). Tourmaline samples from Mandrolisai igneous massif were chemically and structurally investigated by electron microprobe analysis, single-crystal X-ray diffraction, Mössbauer, infrared and optical absorption spectroscopy. Tourmaline aggregates occur both as large crystals displaying graphic textures with quartz, in aplite layers and pegmatite dykes within tonalitic granodiorite, and as fine-grained assemblages, in tourmalinite veins crystallized along fractures within metamorphic country rocks. Tourmaline was identified as schorl in pegmatites and as dravite in veins, both with relevant foitite and magnesio-foitite components. Petrological and mineralogical constraints based on mineral oxythermobarometry and tourmaline crystal chemistry converged towards crystallization temperatures in the range 650-400 °C at about 2.2 kbar, under NNO conditions that remained almost unvaried during the whole magma crystallization path. In the reconstructed scenario, Mandrolisai tourmaline recorded the late stages of consolidation of a single granodioritic magma batch, whose crystallization path locally led to residual concentration of B in the melt. Due to melt/hydrous fluid immiscibility processes, B enrichment promoted the crystallization of the large tourmaline + quartz assemblages in pegmatites. Late B-bearing fluids triggered metasomatic reactions and favored the precipitation of fine-grained tourmaline in tourmalinite veins under a brittle solid-state regime, which overprinted a fracture network of the country rocks previously formed under magmatic flow conditions. Mandrolisai granodiorites are metaluminous (ASI = 0.93-0.95), that is far from the compositional characters of typical B-bearing magmas, mostly felsic and markedly peraluminous (ASI > 1.2). The uncommon occurrence of tourmaline-bearing rocks in Mandrolisai may be an evidence of the limited control exerted by AlO saturation on the origin of tourmaline. Conversely, a more important role of B contents, likely coming from crustal sources, may be invoked for tourmaline saturation in the magma.

Thermal behavior of afghanite, (Na15K5Ca11)?31[Si24Al24O96](SO4)6Cl6, P31c, a = 12.7961(7) Å, c = 21.4094(13) Å, an eight-layer member of the cancrinite group, has been investigated by combined electron microprobe analysis, X-ray single-crystal diffraction, and high-temperature X-ray powder diffraction. Non-ambient X-ray powder diffraction data were collected in the 323-1223 K thermal range on a specimen from Case Collina, Latium, Italy. Structural refinement and site assignment based on the bond-valence analysis, performed on room-temperature single-crystal X-ray diffraction data, provided more accurate site allocation of cations than the available model in the literature. The results show that the cancrinite cages alternating with the liottite cages are more compressed along the c-axis than the remaining ones. As a result the chlorine atom, located at the center of the cages, is driven off-axis to release the steric strain due to the cage compression. Thermal expansion shows a discontinuity at 448 K for both a and c unit-cell parameters, a feature previously reported for other cancrinite-like minerals. Up to 448 K, the c-parameter expands significantly and more than the aparameter. A further discontinuity has been detected at 1073 K for the c-parameter. Mean linear and volume thermal expansion coefficients (×10-6 K-1) in the 323 < T < 448 K thermal range are ?a = 12.9(4), ?c = 17.9(9), and ?V = 43.7(18). Above this discontinuity temperature, the thermal expansion is reverted becoming greater for the a-parameter. Mean linear and volume thermal expansion coefficients in the 448 < T < 1073 K thermal range are ?c = 8.22(3), ?c = 3.52(4), and ?V = 19.68(8). In the 1073 < T < 1223 K thermal range the values are ?a = 6.35(9), ?c = 5.02(14), and ?V = 17.74(9). Afghanite shows a significant microstrain at RT that increases up to ca. 700 K and subsequently decreases as a function of T. Cooling to RT allows a significantly release of ?0 microstrain, which is coupled with a significant expansion of the c-parameter as compared to the starting RT data. The expansion of the c-parameter has been mainly attributed to the full expansion of the cancrinite cages alternating with the liottite cages. Upon reheating at 1173 K, the microstrain increases back to approximately the same value calculated for the first heating process. Repeated heating-RT-cooling cycles led to the partial afghanite structure disruption and the partial conversion, via an intermediate disordered phase, to haüyne. As repeated heating/cooling cycles did not modify the ?0 values both at RT and at HT, it can therefore be concluded that the strain release occurs prevalently during the first heating/cooling cycle.

Thermal behavior of afghanite, (Na15K5Ca11)Sigma(31)[Si24Al24O96](SO4)(6)Cl-6, P31c, a = 12.7961(7) angstrom, c = 21.4094(13) angstrom, an eight-layer member of the cancrinite group, has been investigated by combined electron microprobe analysis, X-ray single-crystal diffraction, and high-temperature X-ray powder diffraction. Non-ambient X-ray powder diffraction data were collected in the 323-1223 K thermal range on a specimen from Case Collina, Latium, Italy. Structural refinement and site assignment based on the bond-valence analysis, performed on room-temperature single-crystal X-ray diffraction data, provided more accurate site allocation of cations than the available model in the literature. The results show that the cancrinite cages alternating with the liottite cages are more compressed along the c-axis than the remaining ones. As a result the chlorine atom, located at the center of the cages, is driven off-axis to release the steric strain due to the cage compression. Thermal expansion shows a discontinuity at 448 K for both a and c unit-cell parameters, a feature previously reported for other cancrinite-like minerals. Up to 448 K, the c-parameter expands significantly and more than the aparameter. A further discontinuity has been detected at 1073 K for the c-parameter. Mean linear and volume thermal expansion coefficients (x10(-6) K-1) in the 323 < T< 448 K thermal range are (alpha) over bar (a), = 12.9(4), (alpha) over bar (c) = 17.9(9), and (alpha) over bar (v) = 43.7(18). Above this discontinuity temperature, the thermal expansion is reverted becoming greater for the a-parameter. Mean linear and volume thermal expansion coefficients in the 448 < T < 1073 K thermal range are (alpha) over bar (c) = 8.22(3), (alpha) over bar (c) = 3.52(4), and (alpha) over bar (v) = 19.68(8). In the 1073 < T < 1223 K thermal range the values are (alpha) over bar (a) = 6.35(9), (alpha) over bar (c) = 5.02(14), and (alpha) over bar (v) = 17.74(9). Afghanite shows a significant microstrain at RT that increases up to ca. 700 K and subsequently decreases as a function of T. Cooling to RT allows a significantly release of epsilon(0) microstrain, which is coupled with a significant expansion of the c-parameter as compared to the starting RT data. The expansion of the c-parameter has been mainly attributed to the full expansion of the cancrinite cages alternating with the liottite cages. Upon reheating at 1173 K, the microstrain increases back to approximately the same value calculated for the first heating process. Repeated heating-RT-cooling cycles led to the partial afghanite structure disruption and the partial conversion, via an intermediate disordered phase, to hatiyne. As repeated heating/cooling cycles did not modify the epsilon(0) values both at RT and at HT, it can therefore be concluded that the strain release occurs prevalently during the first heating/cooling cycle.