APPENDIX. 



288 A. Aspidolite.— Aspidolith, F. v. Kobell,' Ber. Ak. Miinchen, March. 6, 1869. 



Orthorhombic: in prisms giving approximatively 120' and 60°. The smaller sides show 

 reentering angles from twinning, or an aggregation of several crystals, giving the base an 

 oval shield-like appearance. Optically biaxial, with the divergence angle ll = 55' for the 

 red rays. Bisectrix normal to cleavage plane. H.=l— 2. G.=2"72. Lustre pearly, sub- 

 metallic. Color olive-green, in thin leaves brownish-yellow. Foliated, leaves flexible, but 

 not elastic. An analysis afforded von Kobell : 



Si 



Mg 



Fe 



Na 



K 



H 



10-50 



26-30 



9 00 



4-77 



2-52 



1-33=100-86 



46-44 



The oxygen ratio of £, 8, and Si is 14-16 : 4"91 : 24'66, or 3 : 1 : 5. The composition 

 approaches that of a soda phlogopite. 



B. B. exfoliates like verrniculite, giving water in the closed tube. In the forceps diffi- 

 cultly fusible to a dirty gray-white glass. Entirely decomposed by muriatic acid, leaving the 

 silica in pearly scales. 



Found in Zillerthal, in Tyrol, associated with chlorite. 



238. Asteroite—K. name given to a variety of stellate radiated pyroxene, from Nordmark, 

 in Sweden, by L. J. Igelstrom (B. and H. Ztg. xxix. 8, 1870). It is ash-gray to white in 

 color, has a silky lustre, is opaque, becomes bronze color on exposure. Analysis gave Si 

 48-48, Fe 22-24, Mn 4-12, Ca 17'00, Mg 448, ignition 2'83=98-85. The oxygen ratio of 

 & to Si is 1:2. It is a pyroxene near hedenbergite, but containing a portion of the iron 

 replaced by manganese. 



415 B. Aquacreptite. — G. U. Shepard, Am. J. Sci. II. xlvii. 256. 



Massive, occurring in irregular polyhedral fragments, with flat or concave surfaces. 

 H. =25. G. =2 - 05 — 2'08. Lustre dull. Color yellowish-brown. Streak orange-yellow. Brit- 

 tle. Adheres to the tongue. Falls to pieces in water, with a crackling noise. 



Analyses — 1. C. U. Shepard; 2. J. H. Eaton (L c.) : 





Si 



Si 



Mg 



Fe 



H 



1. 



41-00 



4-00 



17-60 



13-30 



23-00=98-90 



2. 



43-03 



556 



19-58 



12-30 



1740=97-87 



Decomposed by muriatic acid. Found in a vein in serpentine, at Westchester, Pa. It is 

 near hydrophite. Needs further investigation. 



732 A. Bastnasite. Euot, Min. i. 296 (1841). Basiskfluorcerium, Hisinger, CEf. Ak. 

 Stockh., 1838, 189. Hamartite, A. E. Nordenskiold, (Ef. Ak. Stockh., 1868, 399. 



The so-called basic fluorid of cerium, from Bastnas, examined by Hisinger, has been 

 reexamined by A. E. Nordenskiold, and shown to be a' fluo-carbonate. As the name basic 

 fluorid, or hydrofluocerite, conveys an incorrect idea of the composition of the mineral, 

 Nordenskiold gives it the new name hamartite, overlooking the fact that Huot had already 

 named the mineral bastnasite, after the locality. 



Orthorhombic ? — Found in small masses imbedded between allanite crystals. Shows dis- 

 tinct cleavage. H=4 Gr.=4 - 93. Lustre greasy. Color wax-yellow. 



Composition Ce F + 2 (Ce, La) C=La 4615, Ce 3'87, Ce 21*12, C 20'20, F 872=100. 

 Analysis by Nordenskiold (1. c.) — 



C La Ce H F— O 



19-50 45-77 2849 1-01 (5 23) =100 



Nordenskiold, having shown by direct determination that but l'Ol per cent, water exists 

 in the mineral, and that the balance of loss on ignition is carbonic acid, finds, on recalcu- 

 lating Hisinger's earlv results with this correction, a close correspondence with the above, 

 viz., La, Ce, 7359, C, H 1941, F— O, 5-76, Si 1-25=99-71. The direct determination of 

 fluorine by Hisinger gave 9 '95 per ct. 



In the closed tube gives but little water, blackens, then becomes whitish-yellow and 

 opaque ; also gives a weak reaction for fluorine. Infusible. With acids effervesces slightly. 

 With sulphuric acid gives off fluohydric acid, even after ignition Found only at the Bastnas 

 Mine, Riddarhyttan, Sweden. The percentage composition brings this mineral near kisch- 

 timite (p. 703). It also resembles kischtimite in some of its physical characters, and further 

 investigation may prove these minerals to be identical. 



