B. Silliman—Mineralogical Notes. 205 
matter (=0°38 per cent) in the mineral—chiefly clay, gives it a 
prevailing shade of yellowish gray. Its hardness is below, that 
of calcite ; luster vitreous ; fracture conchoidal to hackly. 
Oceurring i in an almost rainless country, it has suffered little 
change, small portions only at surface being altered to a dry 
white powder of exanthalose, Na, 
As this is, so far as known, the only locality of this species 
where it exists in grea t abundance, I have taken steps to 
secure all the ei available respecting it. Mr. Thos. 
F. Hopkins, of Vulture, Arizona, has forwarded to me the 
aa eng statement which I present in his own words, in a 
letter date 
“Vurtruxe Mine, A. T., June 18, 1881. 
“Mr. Boyd, a resident of the Verde Valley during the past five 
years, is quite familiar with the large thenardite deposit, aNd fur- 
‘The ‘Salt Mine,’ as it is popularly called, is situated about 
~ Tt « occurs on a ‘bench’ about afte or ce feet, above the 
Verde River, and itself forms one of a series of oo gradually 
sloping toward the river. The de eposit il out boldly in the 
face of the bank, and seems to extend along a distance of ‘fet 
eight hundred to one thousand feet. It met in a white chalky- 
looking for phat and the surface opening is probably about ten 
Fro 
feet wide. this opening immense masses have been carried 
a during more than five years past, every rancher of the dis- 
trict taking off huge wagon loads for t of his stock, ete 
The deposit is solid, and is removed by blasting. It is not under 
water at any time, for both its ed situation and its elevation 
above the river forbid such a condit 
“No systematic openings of the deposit have ever been made, 
and hence its extent is not known. It is simply ‘ gouged out? 
avons Bos: to the whim and convenience of each new comer; but 
seems practically inexhaustible. 
I am informed by several persons who have seen this thenar- 
dite used for the salting of cattlk—among them my friend Mr. 
James Douglass, Jr., who was recently in that portion of 
Arizona—that the animals resort to it very freely, licking it as 
they are wont to do common salt, and with only good results, 
henardite has been found in Nevada and elsewhere in the 
arid regions of the West Coast, hd not before in sufficient 
quantity to be of commercial importa 
G. vom Rath (Zeitsch. f£. Kryst.,) a lately named Lake Bal- 
schasch, in Central Asia, as a locality the flat shores of which 
furnish ‘thenardite i in very considerable quantity. 
New Haven, July 8, 1881. 
