368 Brush and Dana—Farrfield County Minerals. 
: II. Mean. Atomic Ratios 
P05 40°79 40°53 40°66 "286 
Fe,03 12°55 12°67 12°56 “079 
Al,Os 0°10 0-09 0-10 001 
OF. ; 25°27 ). 
MnO 35°83 35°66 35°74 May 160 
Z : : ‘ RRS fag + ie 20 
O in excess 1:20 118 1°19 MnO 164 
CaO 0°13 0°23 0°18 003 
MgO tr tr. r 
Li,O 5°71 5-61 5°66 188 
Na,O 0°53 0-49 008 
H,O ait 3°03 3°07 170 
99°86 99°43 99°65 
Another specimen of the more compact dull gd i analyzed 4 
by H. L. Wells, afforded the following results :—G. =3°26-8:27. 
& ra Mean. Atomic ratio. 
a0 
oat 191 
32°07 31°99 32°03 ) _ MnO; 14°71 ba 
O in excess 1°47 1°50 4s 45 265 
a 4 “TO . 010; . - 
Li, 469 496 4:83 iro 
K,0 0°25 0°28 0°26 "003 
Na.O _ tr. tr. 
H,0 3°32 3°41 Boy 187 
Residue 0:90 0°90 “90 ‘187 
99°86 
This last variety approaches the ROD OnN of a normal phos- 
phate, but as before remarked it is not to be expected that 
such products of alteration ould be homogeneous or prove to 
be definite mineral species. In general the above analyses — 
show a marked ig tice oa with the analogous product of 
and Mallet. The Branchville black material is, however, 
richer in manganese and in lithia, and fortunately we aap it 
of other black Sacompeeicon products bearing no relation to : 
eae Laaese Ma of them contains the oxides of iron and — 
: e 
gentlemen, isis Penfield, Wells and Dewey, who have 
_ assisted us in the chemical part of aaa investigation. 
