Weathering of spodumene in a lateritized pegmatite in Western Australia was studied by investigating in situ samples by electron-beam techniques. The spodumene had mostly altered to smectite. However, some non-crystalline material adjacent to smectite and intermixed with smectite was also observed. No crystallographic orientation between spodumene and smectite was observed by high resolution techniques. The spodumene dissolved to produce etch pits similar to those observed on hornblende grains. The etch pits were almost completely filled with smectite. Most of the Li in the spodumene was lost during its weathering to smectite.

The Palaeoproterozoic (~2.0−1.8 Ga) Stankuvatske Li deposit (Ukrainian Shield, Central Ukraine) represents an uncommon case of recrystallised, fine-grained petalite ± spodumene meta-pegmatite dykes with LCT affinity hosted in amphibolites and meta-ultrabasic rocks. The meta-pegmatite dykes show remnants of primary, pre-metamorphic zoning, with dominant magmatic albite, K-feldspar, quartz, Li-phases (petalite, spodumene, rarely triphylite and montebrasite), and accessory muscovite, fluorapatite, columbite-(Fe), tantalite-(Fe), cassiterite, Ta-rich rutile, zinco- and ferronigerite, gahnite, pyrite, sphalerite and zircon. The parental magma of the meta-pegmatites was peraluminous, and enriched in Li and P, though relatively poor in B and F during the late-magmatic stage. Metasomatic reactions between residual pegmatite magma and (ultra)basic country rocks resulted in the precipitation of holmquistite, triphylite, fluorapatite, tourmaline and Rb–Cs-rich biotite. Secondary generations of fine-grained petalite, spodumene, albite and K-feldspar were formed during post-magmatic stages, i.e. during hydrothermal–metasomatic alteration and/or subsequent tectono–metamorphic recrystallisation of the primary pegmatites. The initial subsolidus metasomatism of primary feldspars took place in alkaline conditions as a result of Na (partly K) for Li exchange.

The presence of fibrolitic sillimanite and chrysoberyl, together with the scarcity of muscovite and (OH,F)-bearing minerals, point to metamorphic recrystallisation of the former Li-rich granitic pegmatites at relatively high-temperature and medium-pressure (~600±50°C; ~0.3−0.4 GPa) conditions.

The paper investigates trace elements and crystal-rich fluid inclusions in spodumene from rare-metal pegmatites of the Kolmozero lithium deposit in the Kola region, Russia. The main lithium mineral in the pegmatites is spodumene, which occurs in three generations, designated as Spd-I, Spd-II and Spd-III. Iron, Na and Mn are the most typical element impurities in spodumene. The Fe/Mn ratio is 7.1 in Spd-I, 12.3 in Spd-II and 13.2 in Spd-III. Spd-II contains fluid and crystal-rich fluid inclusions. The crystal-rich fluid inclusions in Spd-II originally trapped CO2-bearing aqueous fluids with dissolved alkali carbonates. The crystal-rich fluid inclusions contain zabuyelite (Li2CO3) and cristobalite (SiO2) as solid phases, which have not been reported previously from the Kolmozero rare-metal pegmatites. These minerals are assumed to have resulted from a reaction between a CO2-bearing aqueous fluid and host Spd-II and are not related to the mineral-forming system of pegmatites.

The clinopyroxenes kanoite and spodumene were studied by single-crystal X-ray diffraction in a diamond anvil cell (DAC) at room temperature. At the displacive phase transitions between the C2/c and P21/c polymorphs both phases coexist within the same crystal. In this two-phase region the pressure in the DAC remains constant. The experimental results demonstrate that pressure buffering at first-order phase transitions can occur in the DAC.