Apophyllite, analcite, chabazite, prehnite and stilbite are described from pectolite-, chlorite-, calciteand quartz-bearing veins and joint coatings in the late Carboniferous quartz dolerite of the Whin Sill of the northern Pennines. These veins represent the final hydrothermal stages in the sill's emplacement and are not related to the widespread lead-zinc-barium-fluorite mineralization of the...

Mixtures of rare-earth zirconates and aluminates containing Y or + Gd that form a two-phase garnet–fluorite mixture exhibit much slower sintering than pure fluorite at 1400°C. An equivalent Y-free, Gd-containing composition forms perovskite aluminate instead garnet showed faster densification after the metastable decomposes. At 1500°C, Y-free sample also fastest initial rate, whereas there was ...

The article explores English stone-cutting products of the 18th century from Blue John fluorite. objects research are items Mining Museum collection. authors have identified a wide range analogues various collections Russian and European museums, auction houses. considers history development production fluorite; possible workshops been identified. In study determined technical technological fea...

Treatment of Ca or Sr metal with Hg(C(6)F(5))(2) and 2,4,6-trimethylphenol (HOmes) in 1,2-dimethoxyethane (dme) at room temperature resulted in C-F bond activation, giving rise to the unique fluoro(aryloxo)alkaline earth cages [Ca(5)(mu(4)-F)(mu(3)-F)(4)(mu-Omes)(4)(Omes)(dme)(4)] 1 and [Sr(10)(mu(4)-F)(4)(mu(3)-F)(4)(mu-Omes)(12)(dme)(4)] 2, which can be viewed as arrested fluorite structures.

A calcite-rich block in nephelinitic agglomerate at Oldoinyo Lengai comprises Sr-calcite, apatite, fluorite, a Ba-Mn oxide akin to romanrchite, and a distinctive Mn-Fe spinel. Formerly reported as sC3vite, on textural, mineralogical and stable isotope grounds it is now re-interpreted as a highly-altered natrocarbonatite lava. An implication of this study is that natrocarbonatite is not just a m...

Flotation is, doubtless, the most important process among the various techniques used for the treatment of ore. This generalpurpose technique allows the treatment of several complex ores (lead zinc, copper zinc), sulphides (copper, lead, and zinc), oxides (hematite, quartz), oxidized minerals (malachite, cerusite) and even non-metal ores (fluorite, phosphate, coal). Due to the flotation, it is ...