Geology and Natural History. 41 7 



II. Geology and Eatukal History. 



1. New Mineral Names. Brunsvigite, a new Leptochlorite 

 from the Radauthal ; J. Feomme. Brunsvigite is found in the 

 gabbro quarry, "Barenstein IV" on the Schmalenberg in a vein 

 with calcite, quartz, arsenopyrite, chalcopyrite, pyrite, galena 

 and sphalerite. It occurs as thick to fine-leaved masses between 

 the other minerals and also as rounded aggregates in the cavities. 

 Its color is green to dark leek-green and has a gray-green streak. 

 H = 1 — 2 ; G. = 3*0106. The powder is easily decomposed by 

 acids with the separation of pulverulent silica. The analysis 

 gave the following formula ; 6Si0 2 , 2A1 2 8 , 6FeO, 3MgO, 8H 2 0. 

 —Min. u. petr. Mitth. 21, 1902, p. 171-177. 



Pyknochlorite, a new chlorite belonging to the clinochlore 

 group. J. Feomme. In the gabbro quarry, " Barenstein II" on the 

 Schmalenberg occurs a vein formed chiefly of calcite intergrown 

 with quartz. In the interstices between the minerals and binding 

 them together occurs a new chlorite mineral which has been 

 named pyknochlorite. It forms beautiful gray-green solid or 

 micro-crystalline masses. Hardness = 1 — 2, specific gravity = 

 2-8314. With acids only partially decomposed ; before blowpipe 

 yields a black slag. The analysis gives the following formula : 

 10SiO 2 , 4R 2 3 , 17RO, 14H 2 ; R m being chiefly Al with a little 

 Fe, R n chiefly Fe and Mg with small amounts of Ca and Mn. — 

 Min. u. petr. Mitth. 22, 1903, p. 69. 



Liveingite, a new mineral from Binnenthal — R. H. Solly 

 and H. Jackson. The analysis yielded: Pb, 47-58 ; S, 24*91; As, 

 26*93; from which ,the formula, 4PbS.3As 2 S 3 was derived. 

 Liveingite is mon-clinic, y8=89° 45^'. — Proc. Cambridge Phil. 

 Soc. 1901, 11, 239. 



Serendibite, a new borosilicate from Ceylon — G. T. Prior 

 and A. K. Coomaeaswamy. This new species was found near 

 Kandy, Ceylon, in the contact zones between an acid granulite 

 and thin limestone bands. It occurs for the most part in irregu- 

 lar grains of a blue color. Luster is vitreous ; fracture, subcon- 

 choidal ; hardness, 6f; density, 3*42 ; biaxial, probably triclinic ; 

 pleochroism from yellow to blue. The mineral is infusible, 

 unattacked by acids, gives a little water when heated in the 

 closed tube, and when fused with acid potassium sulphate and 

 calcium fluoride gives the green flame of boron. The formula 

 derived from the analysis is : 10 (Fe,Ca,Mg)0, 5A1 2 3 , 6Si0 2 , 

 B 2 3 . — The Min. Mag., xiii, p. 221f. w. e. f. 



2. Zes Richesse Minerales de UAfrique; by L. De Laitnay. 

 Paris, Ch. Beranger, 1903. — This book describes the ore deposits 

 of Africa as they are known and developed at the present time. 

 An outline of the general geology of the continent is given in 

 the early part of the volume and then follow in order discussions 

 of the gold, copper and iron deposits, to each of which a chapter 

 is devoted. Other chapters deal with the occurrence of the 

 various other metals, with the diamond mines, the phosphate, 



