![]() The gneisses have been penetrated in several areas by granite pegmatites with very coarse grains of quartz and feldspar. The area (Figure 1) is underlain by plagioclase gneisses, biotite gneisses and banded gneisses of the Precambrian Basement of South western Cameroon (Dumort, 1968). Ebensuk is found in Upper Bayang Sub-Division 48 km west of Tinto, the Sub-Divisional headquarters. The study is located to the South east of Mamfe in the South West Region of Cameroon between latitude 5° 31′ 24″ N and longitude 9° 48′ 24″ E. Rutile as a high quality titanium mineral is used in three areas including i) in the manufacture of titanium metal ii) manufacture of TiO 2 white pigments and iii) sheathing of welding electrodes for the stabilization of the electric arc, for the reduction of the melting viscosity and for the reduction of surface tension of the metal drops on the electrodes (Elsnar, 2010). The objectives of this work are to identify rutile deposits in the area and to carry out petrographic, granulometric and geochemical characterization of the rutile in order to evaluate its quality according to international specification for commercial rutile. This area that has been little investigated is the subject of this paper. (2012).īesides the Yaounde area, some trade in rutile was reported in Tali close to Mamfe during the Second World War with a chamber of commerce in Europe by Dumort (1968). Some of this research has been reported by Stendal et al., (2006), Ngalla (2009), Sumbele (2011) and Ngalla et al. With the recent renewed interest in the mining sector in the country, there is active exploration and research in the area around Yaounde with the goal of discovering new deposits that could warrant mechanical mining. Cameroon ranked third after Australia and the United States of America in rutile production from 1935 up to 1957 when mining activity in the sector was abandoned. All deposits in this area are alluvial and mining has been artisanal (COLONNA-CIMERA, 1949a, b Callot, 1950 Chataignon, 1951 Champetier de Ribes, 1956 Champetier de Ribes and Robert, 1956 Laplaine, 1969). Rutile has been known to occur in Cameroon since 1908 and was very actively exploited from 1935 to 1957 in the area around Yaounde. Key words: Coarse rutile, geochemistry, high quality, regolith, grain size. The rutile must have been derived through weathering of the underlying gneisses and their coarse nature is probably indicative of a possible source from granite pegmatite veins occurring in the gneisses outcropping in the study area. ![]() The grains are predominantly concentrated in the 16≤Z 96 wt%, and subordinate Fe2O (2.2-3.1 wt%), and minor amounts of Al2O3, SO3, K2O P2O5 and Mn2O3 for all the samples analyzed, and meets international specifications for economic rutile ores. Results of grain size (Z) analysis show that the rutile crystals range in size from 4mm to Z≥32 mm. The rutile is black, longitudinally striated, with a metallic to adamantine luster and hard. The rutile concentration ranges from 2.53 kg/m3 of regolith material in Pit C to 2.83 kg/m3 in Pit B with an average of 2.66 kg/m3. The trick to this is that unlike traditional manga publishing, in which the Japanese publisher gets a license fee up front and the editorial team is paid ahead of time as well, everyone working on the DMG books (including Digital itself) gets their cut on the back end, as a straight percentage of sales.Coarse rutile with some grains exceeding 32 mm was recovered from regolith excavated from three pits (ABC) at Ebensuk. ![]() Two years ago the publisher created the Digital Manga Guild, which uses amateur translators, editors and letterers to localize yaoi manga that is then published digitally. The company is in the process of retooling its digital manga website, and it also publishes digitally via comiXology, iBooks, Kindle and Nook.ĭigital has always been willing to try new things. This may be a sign of trouble, but then again, it may be a sign that Digital is just reacting quickly to market conditions. What's going on here? At the ICv2 Conference in October, Milton Greipp noted a sharp drop in manga sales, although this has not affected every publisher equally. ![]()
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