C. JS. Warren — Mineralogical Notes. 



123 



£sc 



5. Crystallized Tantulite from Paris , Maine. 



There are also in the Brush collection a few small specimens 

 of tantalite received from Mr. L. K. Stone of Paris, and 

 identified by Prof. Penfield. The specific gravity of the crys- 

 tals is very high, 7*26, thus indicating that they are tantalite 

 and not columbite. They contain iron, and little or no man- 

 ganese, which adds to the interest connected with them, since 

 the crystallized tantalite previously described has been of 

 the manganese variety. 10> n 



Only a very little ma- . _, — , — .^^ 



terial was found and it ^iTT^^Tf 

 is not well adapted for 

 crystallographic study 

 as the faces of the crys- 

 tals are dull, but suffi- 

 ciently accurate meas- 

 urements could be 

 obtained to identify 

 the forms, which were 



found to correspond to well-known ones on columbite. The 

 habit of one of the crystals is shown in fig. 10, and fig. 11 

 represents the arrangement of the faces on the corner of 

 another crystal. The forms that were identified were as fol- 

 lows : 



5, 010 



c, 001 



d, 730 



m, 110 



g, 130 



o, 111 



n. 163 



The measured angles are given below, and since the meas- 

 urements coald not be made with sufficient accuracy for 

 establishing an axial ratio for the iron tantalate, they are com- 

 pared with the angles of columbite, derived from the axial 

 ratio established by E. S. Dana.* 





Measured. 



Calculated. 



b*g, 



010/^130 =. 20° 35' 



21° 55' 



b^m, 



010/sll0 = 49 



50 21 



b^d, 



010^730 = 70 15 



70 27 



b^ a, 



010^ 100 = 91 



90 



bs^n, 



010/s 163 = 31 15 



30 50 



»A«, 



163/U63 = 19 30 



19 54 



o^o, 



lll^lll = 61 30 



02 27 



6. Cobaltiferoas Smithsonite from JBoleo, Lower California. 



This mineral was sent to this laboratory for identification, 

 by Mr. Geo. W. Fiss of Philadelphia, and was supposed to be 

 the rare hydrated cobalt carbonate, remingtonite, the composi- 

 tion of which is not known. The mineral consists of little, 



* Zs. Kr., xii, 266. 1886. 



