Eighty-one samples taken from 68 glass beads found in southwestern Poland on sites of the Lusatian culture from the Hallstatt C and Hallstatt D subphases were analysed by EPMA. A subsample of 18 of these were additionally subjected to analysis by means of LA-ICP-MS in order to validate the results obtained by EPMA. Some glass was made using mineral soda and some using plant ash rich in sodium. Both high-magnesium soda-lime glass (HMG) and low-magnesium soda-lime glass (LMG) were identified. A large number of samples are characterized by low MgO content and medium K 2 O content (LMMK glass), combined with low concentrations of CaO and high Fe 2 O 3 and Al 2 O 3 . All the LMMK glass contains numerous silica crystals and inclusions composed of a number of elements (most frequently Cu, Co, Sb, As, Ag, Ni and Fe). The LMMK glass was presumably made in Europe during the Hallstatt C.
The new mineral nabimusaite, KCa12(SiO4)4(SO4)2O2F (R3m, a = 7.1905(4), c = 41.251(3) Å, V = 1847.1(2) Å3, Z = 3), has been discovered in larnite-ye' elimite nodules of pyrometamorphic rocks of the Hatrurim Complex. Nabimusaite is colourless, transparent with a white streak, has a vitreous lustre and does not show luminescence. It is brittle, but shows pronounced parting and imperfect cleavage along (001). Nabimusaite is uniaxial (–), ω = 1.644(2), ε = 1.640(2) (589 nm), nonpleochroic, Mohs' hardness is ∼5 and the calculated density is 3.119 g cm–3. The crystal structure has been solved and refined to R1 = 0.0416. Its artificial analogue is known. The nabimusaite structure may be derived from that of hatrurite, also known as the clinker phase 'alite' (C3S = Ca3SiO5), and is built up by an intercalation of three positively charged hatrurite-like modules of composition [Ca12(SiO4)4O2F]3+ with inserted modules of [K(SO4)2]3–. The hatrurite-like modules in nabimusaite are characterized by octahedrally coordinated anion sites and tetrahedrally coordinated cation sites. The structure is representative of the intercalated antiperovskite type. In contrast to its synthetic analogue, nabimusaite is P-bearing. The shortened bond T–O lengths for one tetrahedral site indicates P preference at the Si2 site, located at the border of the hatrurite-like modules. Significant variations of isomorphous substitutions in nabimusaite suggest the possibility of other isostructural minerals occurring in Nature. It also seems likely that nabimusaite could serve as a prototype for new advanced synthetic materials, given the discovery of two other new minerals in the Hatrurim Complex with related modular structures, placed in the nabimusaite group. These are zadovite and aradite, as described in a companion paper (Galuskin et al., 2015a).The mineral assemblage and paragenesis of nabimusaite suggests that nabimusaite formed as a result of the reaction of potassium-enriched, sulfate-bearing melt with larnite and ellestadite. This contradicts the isochemical model that pyrometamorphic rocks of the Hatrurim Complex formed relatively fast in a practically dry system.
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