DEc., 1908. MINERALOGICAL NOTES 149 
determination as ¢ (9.0.10), although its position, so near that of the 
unit dome common to linarite, would suggest the possibility of its 
being confused with the latter. It may also be noted that the meas- 
urement from a (100) A ¢ (oor), is nearly the same as from a (100) 
A @ (9.0.10). This would suggest twinning on the orthopinacoid, 
but on careful study of the crystal no evidence of twinning could be 
observed. The interpretation given above seems, therefore, to be 
the most reasonable one. The pyramid 7 (523) exhibits somewhat 
rounded faces; the dome wu (201) is also characterized by somewhat 
undulating surfaces. No special characters were noted regarding 
the other planes. The appearance of the crystal as a whole is shown 
iii ty - in: Fig, 3, Pl. L a projection of these forms 
upon the clinopinacoid is shown. This exhibits to good advantage 
the characteristic zones of the crystal and its nearly square appearance 
when seen in the direction of the ortho-axis. The following is a list 
of the forms observed, together with some of the measured and cal- 
culated angles. The new forms are marked with an asterisk. 
aay 4 
(110) = fog at Es 52° 40 
~ 
¢ (oor) +h (Gic..10) , 
a (100) £14 (308 ) 
m (110) u (201) 
P HOLT) Pe ory) 
SOM TOC, 0} HF (523) 
| Observed Caleulated 
ra Nee ma (O01)) A (302) = 20 ets 40° 31%’ 
ce = | (oor) A. (or) = ro” DA" Ron. G6. 
eee a Th = (001) A..(Foo) = 7 to pio ta Be ad oie, 
eho See LOOT), (10,0, 0) = Ae tay gc 0eS! 
eee BeiooT) 2A (9.6.10) ie ge see Ao ke ed 
ram tort) A) (110) = so 45" basis 
ca) == {O11) fA; (100) == ae Ta aoe ea de 
See ==" (211) A (iia) = 42° 50! Je EN it ane 
Pee = (211) A: (oo) = SOR ear SO 27) 
Er A..mM A 
e=12' (523) 
