Geology and Mineralogy. 567 



the preparation of the Third Appendix to that work (]915) as 

 well as those which have been proposed since the Appendix went 

 to press. It is planned to make the descriptive matter given 

 under each name as brief as possible, while still giving the impor- 

 tant facts concerning the mineral. 



The writer wishes to acknowledge the kind assistance of Dr. 

 W. T. Schaller of the United States Geological Survey in the 

 preparation of the following list. 



Alfoanite. C I. lstrati and M. A. Mihailescu, ['Bui. Soc. Sti- 

 inte Bucuresti, xx, 626, 1912]. Chem. Centralbl., i, 1587, 1912".— 

 A black organic substance with a resinous luster. G. = 1*644. 

 Fuses with intumescence between 85° and 110°. Burns with a 

 sooty flame. Yields water at 110° and a large amount of gas 

 between 195° and 305° ; above 305° a } r ellow liquid distils over. 

 Found in Albania. 



Allimogel. O. Pauls, Zs. prakt. Geol., xxi, 545, 1913. — Name 

 suggested for the amorphous hydroxide of aluminium forming 

 the main constituent of bauxite. Same as sporogelite, diasporo- 

 gelite, etc. 



Amljatoariuite. A. Lacroix, Bull. Soc. Min., xxxviii, 265, 

 1915. — A carbonate of strontium and the rare earths, prob- 

 ably 5SrC0 3 .4(Ce,La,Di) 2 (C0 3 ) 3 .(Ce,La,Di) 2 3 . Orthorhombic ? 

 Occurs in crystals which are often arranged with parallel axes, form- 

 ing skeleton -like groups. Prismatic angle about 95°. Optically 

 negative. Acute bisectrix parallel to vertical axis. Axial plane 

 parallel to (010). Refractive index greater than 1*658. Bire- 

 fringence about 0*08. Occurs intimately associated with celestite, 

 calcite, monazite, quartz, etc., at Ambatoarina, near Ambositra, 

 Madagascar. 



Arseno-foismite. A. H. Means, this Journal, xli, 12V, 1916. — 

 In cryptocrystalline aggregates. Color, yellowish green with 

 tinge of brown. G. = 5*70. Refractive index about 1*60. Formula 

 proposed as either 2Bi 2 3 .As 2 5 .2H 2 or 4Bi 2 3 .3As 2 B .5H 2 0. 

 Occurs in impure condition with barite, limonite and small 

 amounts of other minerals in the Mammoth mine, Tintic district, 

 Utah. 



Aurobismuthinite. G. A. Koenig, J. Ac. So., Philadel- 

 phia, xv, 405, 1912. — A sulphide of bismuth, gold and silver, 

 (Bi,Au,Ag 2 ) 6 S 6 . Granular, massive. Color, light gray. Soft. 

 Unknown locality. 



Bassetite. A. F. Hallimond, Min. Mag., xvii, 221, 1915.— 

 From Basset group of mines, Cornwall, previously considered to 

 be autunite. Monoclinic ; a : b : c = 0*3473 : 1 : 0*3456 ; /3 = 

 89° 17'. Twinned ; tw. pi. £(010), the a and c axes being inter- 

 changed. Cleavage parallel to 5(010), a(100), c(001). G. = 3*10. 

 Color yellow. Transparent. Biaxial, negative. 2E = 110°. 

 Ax. pi. within acute angle, /3, inclined 4° to c axis. /3 = 1*574, 

 y = 1*580. Pleochroic, /3 = y deep yellow, a pale yellow. In the 

 desiccator the extinction an^'le increases to about 20°. Comp. — 

 Probably Ca(U0 2 ) 2 (POJ 2 .8H 2 0. Soluble in acids. 



Belbaite. W. Yernadsky, Zs. Kr., liii, 283, 1913.— See under 

 Elbaite. 



