131'i Journal of Applied Microscopy 



NOTES ON RECENT MINERALOGICAL 

 LITERATURE. 



Alfred J. Moses and Lea McI. Luquer. 



Books and reprints for review should be sent to Alfred J. Moses, Columbia University, 



New York. N. Y. 



Clarke, p. W. The Constitution of Tourma- Recent investigations of Penfield and 

 line. Am. Jour. Sci. iv, 8 : in, 189Q. Yoote have led the author to modify in 



some particulars his formula; proposed in 1895. 



Clarke regards all tourmalines as derived from the alumino-boro-silicate acid 

 Hj^Al^BgSigOg, with all the H atoms replaceable by bases. Using the formula : 



AlgCSiOJe (B02)2. BO3H2.H,., 

 which is applicable to the discussion of the analyses, the author shows that the 

 results of analyses can be expressed by the combination of diiiferent molecules, 

 which are all derived from the general formula by the substitution of different 

 bases for H. For example, the composition of the brown Gouverneur, N. Y. 

 tourmaline corresponds to the following molecular mixture : 



5. A\, (SiOJe (60^)2 • B03Ca . Mg,H„ 

 3. Al2(Si04)6(B02)2 . BO.Mg. Mg^H^, 

 2. Al2(Si04)6(B02)2 . BOgNaH . Al2Na2H4. 

 An elaborate chemical discussion is given and many examples cited. 

 Future investigations may prove tourmaline to be derived from a complex 

 boro-silicic acid ; hence the constitution must still be regarded as unsettled. 



L. McI. L. 



„ , „, ., -, TVT i,T • T The occurrences are of the usual type, 



Foote, W. M. Note on a New Meteoric Iron, -'. 



found near the Tombigbee River, in Choc- the disintegration of the iron being 

 tow and Sumter Counties, Alabama. Am. rather marked. Schreibersite was found 



Jour. Sci. IV, 0: 153, 1099. 



to be present. The plessite in one 

 specimen exhibited, under etching test, a beautiful phenomenon suggestive of a 

 metallic sun-stone. 



The course of the meteorite must have been from N to S ; as after breaking 

 up the fragments were found in this direction, the smaller having fallen first. 



L. McI. L. 



Foote, W. M. Note on a New Meteoric Iron Resembles most siderites, but Wid- 

 found near Iredell, Bosque Co., Te.xas. Am. mannstatten figures did not appear on 

 Jour, iv, 8: 415, 1899. . , , ,, ,• • r ,, 



etching, hence probably a distinct tall 



from the other meteorites of that region. L- McI. l. 



Termier, P. Sur la composition chimique at les The general description is given in a 

 proprieties optique de la leverrierite. Bull. previous article. 

 Soc. Min. 22, 27, 1899. . . ' 



Analysis gives : 



SiOj AI2O3 FegOg MgO CaO K2O loss by calcination (nearly all H2O) 



49.90 37.02 3.65 0.30 tr. 1.13 8.65 = 100.65, 



yielding formula (H2, K2)0 . AI2O, • 2Si02, somewhat similar to that of 



Muscovite. G. = 2.6. Axial angle varies from 0°-50°,but is generally small. 



