Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-01-29
MONTANA. SAPPHIRES
MOUNTAIN sTaTE HAS WEALTH
OF RARE STONES.
Famous Gem M4e-5ewels Found in
Igneous ! ck-Luck of
Gold Hunter.
From the Butte Miner.

| From the Butte Miner
| In Fergus county, are located the most
famous gem mines oIyth North American
continent They ersf situated in the Yogo
mining district, about sixteen miles from
| the town of Utica. IT was the everlasting
search for gold which led to their discovery.
A placer mining company was organized in
1895 to work the gold gravel east of
the Yogo forks of the Judith river The
company put in SIS, coo worth of ditch and
fumes. but after all this outlay the first
seasons cleanup amounted to only $TO0.
| But in the sluice boxes were number of
blue stones which were later identified as
| sapphires. A cigar box full of these stones
4 was sent east and Tiffany gave SIS, 150 for
| them. The company now saw some results
| in sight for its great outlay, and made
preparations to work the gravels for the
sapphires. which were found in great abund-
ance in certain parts of the field. At first
| 1t was thought that the gems, with the gold,
| came from Yogo gulch, but in February,
| 1896, their real source was discovered by
| John Ettien of the neighboring valley of the
Judith river.
While prospecting above the placer he
| found a fissure in. the limestone with a
So filling. which resembled the outcrop of
| a vein Some of the dirt was washed and
| there again were the blue stones. Their
value again was not known by the discov-
erer until they were shown to the workers
at the placer. They began at once to locate
| the sapphire lead. = Investigation showed
| that the gems occurred in a dixie of trap
rock which could be traced for a distance Of
| five miles from the meadows of the Judith
river westward to the canyon of Yogo ere k.
| Its entire known extent was located as lode
| claims, some of which have already been
patented. The sapphire mines are in the
on three sides by the Little Belt mountains.
| whose slopes disclose outcrops of white
| limestone resembling banks of snow High
| foothill ridges shut in the basin from the
IN hn an -h,o,,
| basin flows the Jud IN river it's three forks
uniting at the base of the mountain slopes
| to the west. The mines take their name
| from Yogo creek the most northerly fork
| of the river. They are located on the bare
benchland lying north of the main streams
and east of the creek.
Embedded in Rock.
| 1t is an igneous rock. or clay, SO hard
| that it requires drilling and blasting, that
the. precious gems are found. This rock
Stacks pretty much the same as lime upon
exposure to the air, the process being aided
| by rain. frost and snow. Then it is run
through the sluice boxes. some of il two or
| three times before the gems are extracted.
The gems in the rough just as taken from
the mines, are carefully sorted and shipped
TO the London house. and there prepared
| for the market. The product is sold in the
European. Asiatic and New York markets
and the superior quality of the stone found
IN Fergus county is said to be driving the
| Queen Victoria had Yogo sapphire in her
collection of gems: at the Paris exposition
the Yogo sapphires were awarded a silver
medal. Another great concern owns large
number of claims andit output is nearly
| if not quite. equal to that of the other cor
poration 1t maintains it's own shop in
Helena. where fifteen men are employed
cutting and polishing the stones, and it is
asserted with confidence that the work done
| there is finer even than that turned out IN
London. q z4g
In recent report of the Montana bu-
| reau of agriculture labor and industry
the following description of the methods
of working the mines occurs: 1.-THE method
of extracting the sapphires from the mag
ma is somewhat similar to that used by
placer miners in Sluicing for gold The
sluice boxes are fitted with Hungarian riff
fies, as in placer mining, but it is necessary
! to, exercise more care in setting them, as
| the specific gravity of the sapphire is much
less than that of gold and with the boxes
set at too great pitch they would pass
over the rifles and be lost. When first at
tackled the magma is passed over a grizzly
(screen and the finer parts pass at once
into the sluices. The coarser. harder ma
terial is thrown into the dump. where the
process of disintegration takes place. This
process occupies from one month to one
year. according to the hardness and tenac-
ity of the magma. Superintendent Swee-
ney of the American company assists the
elements in the dsintegration of his dumps
by turning a flow of water on them occa-
of the vein matter is ready to pass through
the sluices in two months. For cleaning UP
an ordinary rocker is used. with three
screens of as many sizes, through which
the pay dirt is passed.
Planning the Gems.
When the pay dirt has been worked
down as closely as possible in the rocker
it is PANIED in one of the finer screens.
dried and the stones picked by hand from
the small amount of gravel remaining. All
the stones saved. the larger, perfect
ones being valuable as gems the smaller
ones being used as watch jewels and in
other fine mechanical work: the imperfect
ones are ground and mixed with diamond
dust and used in gem-cutting and fo- pol
iShing purposes, when the product is known
as emery. The stones of the YOgO vein
vary in size from the smallest to four or
five karats and as gems they equal in val
ue the best products of the mines of Ceylon
and Burmah. The largest stones yet found
in the American gem company's mines was
| taken from the Fourth of July claim, and
| weighed eight karats. and that taken from
the new syndicate mines weighed little
| more than nine karats The stones are very
evenly distributed throughout the vein but
are less broken and somewhat better form
ed in the deeper workings. although some
of the most valuable stones yet found were
from the surface. The sapphire color is
blue and the shade known as cornfiower
blue is the most highly priced Occasional
ly stones very nearly approaching the ruby
are found in the Yogo vein, but they are
usually imperfect and worthless as gems"