A speedy and accurate staining procedure for the quantitative determination of the feldspars in rocks and sands of soils is proposed. The minerals are treated, by direct contact, with 48 per cent hydrofluoric acid, and then immersed in a concentrated sodium cobaltinitrite solution which stains the potash feldspars yellow. This treatment is followed by immersion in a buffered hematein solution which stains the plagioclase feldspars purple. The depth of colour on the plagioclase depends upon the position in the isomorphous series. Quartz, gypsum and calcite are not affected by the treatment.The quantity of the potash and plagioclase feldspar present is then easily determined by grain counts under the petrographic microscope.

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The subvolcanic True Hill granite porphyry in southwestern New Brunswick is genetically related to the Beech Hill series of granites of Devono-Carboniferous age. Three True Hill (TH) greisenised granite porphyry cupolas host Bi-Sn-Mo-W mineralized zones that have similarities to the nearby W-Mo-Bi orebodies at Mount Pleasant (MP).Tin-bearing lodes (0.03 to 0.66 wL % Sn) are developed along faults and fractures that cut both mineralized (Bi-Sn-Mo-W) and unmineralized True Hill granite porphyry and enclosing metasedimentary rocks of the Waweig Formation. Within these lodes, particularly the central Main lode, two types of mineralization are present, an early chlorite-sulfide assemblage (Stage 1) and a later hematite-phengite-cassiterite assemblage (Stage 2) that replaces, in part, the earlier Stage 1 assemblage. The Stage 1 assemblage consists of Fe-rich septechlorite, pyrite, low-Fe sphalerite, magnetite, chalcopyrite, galena, Pb-Bi sulfides, tennantite, arsenopyrite and native Ag. Fe-Mg-Mn metasomatism responsible for chloritization was coincident with leaching of alkali and alkali-earth elements during feldspar hydrolysis. The Stage 1 assemblage (chl-sulfide) was formed at low temperature (<200°C) and low oxygen fugacity. The Stage 2 assemblage includes hematite, phengite, cassiterite and monazite with minor late quartz and fluorite. This assemblage was deposited at slightly higher temperatures (200p-300pC), higher oxygen fugacity (above hematite-magnetite buffer) and at moderate pH 's (

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Integrated geological, geochemical, and geophysical data for the posttectonic granitic rocks of the North Pole, Burnthill, Dungarvon, Trout Brook, and Rocky Brook plutons and surrounding areas were examined to assess their potential for uranium mineralization. Geological, geochemical, and geophysical criteria that are thought to be useful guides for uranium exploration were also established for the host granites. The granitic plutons were emplaced discordantly, late in the tectonomagmatic sequence and at shallow depths within the metasedimentary rocks of the Miramichi Anticlinorium. Geochemically, the host granites are highly evolved (Si02 &amp;gt; 75 wt. %), peraluminous and have strong similarities with ilmenite-series 'S-type' and 'A-type' granitoids. Uranium occurrences are spatially and perhaps temporally associated with late-phase differentiates of the plutons where elevated levels of other lithophile elements such as Sn, W, Mo, and F were also detected. Geophysically, the granitic plutons are associated with distinctively high aeroradiometric eU, eTh, and K anomalies that coincide with strong negative Bouguer anomalies and low magnetic values. Conceptual models involving magmatic and hydrothermal processes have been adopted to explain the concentration of uranium and associated metals in the granitic plutons.