pbatt.] CORUNDUM GEMS. 47 
occurs very sparingly here, although the yellowish and Light-green 
colors arc aot uncommon. What is probabty the finest known speci- 
men of the oriental emerald in the world came from this mine, and is 
now iii the Benienl collection. It is a crystal t by 2 by 1| inches; part 
of il is transparent, and several very fine gems could be cut from it. 
At the Sapphire and Whitewater corundum mines, near Sapphire, 
Jackson ( bounty, N. C, fragments of sapphire of a fine blue color have 
been found, from which small bui good gems have been cut. 
Associated with the green amphibolite rock near Elf post-office, 
(May County, N. C, deep-blue sapphires have been sparingly found. 
These bear the same relation to the amphibolite as the red ami pink 
sapphire described on page r>. 
MONTANA S W'I'IIIKKS. 
The onl\ systematic mining that has been undertaken for sapphires 
is in Montana. Sapphires were first found in this State by miners 
who were washing the gravels of the bars on the Missouri River, to the 
east of Helena, for gold. These were firsl described in L873 by J. Law- 
rence Smith, 1 luii it was not until L891 thai actual mining was begun. 
During t hat year a number of companies were organized to work these 
bars for sapphires. 
These bars are Located from 1 1' 1o is miles east and northeast of 
Helena, and have been followed for a distance of about L2 miles from 
Canyon Ferry down the river to American liar. At various intervals 
these bars have been worked for the sapphires and are designated by 
the following uames, starting with the one thai is farthesl up the 
river: Emerald Bar, Cheyenne liar, French liar, Spokane Bar, Met- 
ropolitan liar, Ruby Bar, Eldorado liar, Dana liar, and American liar. 
The location of these bars is shown on the map (1*1. IV). 
A few sapphires have been found as far down the river as Beartool h, 
but sapphires have uo1 been found in large quantity below American 
liar. 
Above Emerald liar there have been no sapphires found on any of 
the bars, but in the gravel of Magpie Gulch, less than a mile above 
Emerald liar (at Canyon Ferry), many sapphires have been found 
by miners who were washing the gravel tor gold. No sapphires have 
been found in situ in this gulch, but Kunz 2 has noted the occurrence 
of sapphires that were found in a dike of vesicular mica-augite- 
andesite which was about 6 feet wide and cut through the green 
slate below the gravels. In the gravel deposits at French Bar, about 
3 miles below Canyon Ferry, a narrow dike was encountered last 
summer, 3 to G feet in width, that had greenish sapphires scattered 
sparingly through it. 
This dike was encountered about 50 feet above the river and its 
1 Am. Jour. Sci., 3d series, Vol. VI, 1873, p. 185. 
2 Min. Mag,, Vol. IX., 1891, No. 44, p. 396. 
