•±24 Palache — Notes on Tellurides from Colorado. 



like that found in the sylvanite crystals was also present in 

 goldschmidtite, giving rise to the many apparently new forms 

 referred to above. And a comparison of the measurements 

 and projections finally proved that this was the case for most 

 of these forms. The following table shows the sylvanite 

 forms equivalent to those observed on goldschmidtite. It will 

 be observed that it is divided into three parts containing (1) 

 forms given by Hobbs and reobserved by the author; (2) forms 

 observed by the author only ; and (3) forms given by Hobbs 

 which were not observed on any of the author's material 

 and which lead to new forms for sylvanite. 



(1) I (2) (cont'd) 



Forms observed by Hobbs and Palache. | Additional Forms observed by Palache 

 Goldschmidtite. Sylvanite. : Goldschmidtite. Sylvanite, 



Letter. Symbol. Letter. Symbol. 



c 



b 



a 



9 



f 



m 



k 



w 



n 



s 



S 



jsr 

 w 



001 

 010 

 100 

 310 

 210 

 110 

 032 

 401 

 201 

 101 

 101 

 201 

 401 



N 



b 



m 



t 



r 



s 







n 



c 



(L 

 a 



G_ 



n 



201 



010 



101 



323 



111 



121 



231 



201 twinned 



001 



100 twinned 



100 



001 twinned 



201 



(2) 



Additional Forms observed by Palache. 

 Goldschmidtite. Sylvanite. 



Symbol. 

 134 

 1 12 

 230 

 120 

 832 

 532 

 532 

 734 



102 



Letter. Symbol. 



J 321 



k 521 



O 131 



q 141 



I_ 211 twinned 



i 321 



£ 321 twinned 



j 521 twinned 



M 101 



(3) 



Forms observed by Hobbs not confirmed 

 by Palache and yielding new sylvanite 

 forms. 



Goldschmidtite. 



Symbol. 



232 



232 



434 



434 



212 



212 ' 



131 



234 



132 



132 



Letter. Symbol. 

 e 110 



e 110 twinned 

 210 



210 twinned 

 310 



310 twinned 

 120 



111 twinned 

 121 

 121 twinned 



/ 

 / 



9 



_g 



R 



P 



Letter. 

 t 

 I 

 V 

 X 



r 



Symbol. 

 370 

 130 

 35-0-1 



io-o-i 



801 

 703 



y 508 



X io-o-i 

 z Ti-o-i 



Sylvanite. 



Symbol. 

 292 

 161 



9-0-10? 

 403 twinned 

 203 



2-0-25 or 

 301 twinned 

 708 or 

 801 twinned 

 403 

 504 



The forms in (3) appear to need confirmation before being 

 added to the sylvanite series as the following considerations 

 will show. ISTone of them was observed by the author on the 



