I did not visit Guye"s other mine, which lies high, perhaps 3,000 feet above Middle Fork. Mr. Guye represents it as similar in character to the bed elsewhere, with the addition of some brown and red ore. The other deposits mentioned I received no description of.
[Sidenote: All easily reached from Seattle, Lake Sh.o.r.e and Eastern Railway.]
None of these mines have been developed beyond the uncovering of a face.
As yet there is no furnace for smelting them, and no means provided for bringing them off the mountains. There is no difficulty about reaching them with spur railroads and inclined planes. It has occurred to me as possible that a narrow gauge railroad might reach all of these mines, without heavy grades, by starting at the highest point of the Lake Sh.o.r.e road and following the divides from mountain to mountain. This, however, can only be determined by a special reconnaissance.
[Sidenote: Cle-ellum ore beds.]
There are large deposits of iron ore also on the east side of the Cascade Mountains, not far from the crest line, on the waters of the Cle-ellum River. Three distinct beds are reported. They are all in the valley of the Cle-ellum River. The upper bed is situated about eight miles above Cle-ellum Lake, on the main and east fork of the Cle-ellum River. This bed has been described to me by Mr. Whitworth and Mr. Burch.
The distance from the Northern Pacific Railroad is twenty-five miles, following the Cle-ellum valley. It is within sixteen miles of the most distant location made of the Seattle, Lake Sh.o.r.e and Eastern Railway; and by another route which has been spoken of, this railroad would pa.s.s close to the ore bed. Mr. Whitworth says concerning it: "The ledge is well defined, and is traced and located about two miles, its course being nearly north and south. It is apparently from forty to sixty feet in width, and pitches at about an angle of 20 to the west. The casing rock is porphyry. The deposit is evidently extensive. The ore appears rich, is magnetic, and is reported to a.s.say from 56-1/2 to 66 per cent.
I obtained samples of the rock, from which satisfactory tests can be, no doubt, obtained."
The elevation of the iron ore outcrop is estimated at 3,000 feet, which would place it nearly on a level with the summit of Snoqualmie Pa.s.s; but it is only about 200 feet above the local water-level.
Mr. Burch says concerning this ore bed, which has now been bought by Mr. Kirke for the Moss Bay Company, that the strike of the bed is northeast, whilst the outcrop runs northwest. The ore is in five or more separate beds, each bed being on an average forty to fifty feet thick, and the beds separated by rock. The ore can be followed but a short distance along the strike.
[Sidenote: Burch"s ore bed.]
Burch"s iron ore bed approaches the Cle-ellum River about four miles below the Kirke bed, and extends in a northeast direction to the headwaters of Boulder Creek, a distance of five miles. The outcrop crosses three high ridges. The dip is south, at an angle of 45. The width is at least twenty feet. A ferruginous limestone lies against the ore on the south side. The limestone is 300 or 400 feet thick. It seems to overlie the iron bed. Its outside or top layers are pure blue limestone.
A gray sandstone, rather soft, overlies the limestone, and over this comes a coal-bearing rock in which are d.y.k.es of gray iron ore, some of them standing out of the ground 80 or 100 feet. The magnetic iron ore is a.s.sociated with hornblende and quartzite. All rocks dip south. Mr. Burch says that this ore resembles the Kirke ore, but has some of the characteristics of hemat.i.te. Mr. Guye talks in the same way about his iron ore on Middle Fork.
At one point, not far from Cle-ellum River, a bed of gray iron ore crosses the magnetic ore at right angles. This gray ore is not well understood. It may be an altered copper lode. The main ore bed is more strongly magnetic near the intersection than it is elsewhere.
I may here remark that Mr. Burch reports considerable float of rich magnet.i.te on the sh.o.r.es of Lake Chelan.
[Sidenote: Dudley ore bed.]
I have no description of the Dudley iron ore bed, but it is said to be large, and of the best quality. Its location is also in the Cle-ellum valley, between Burch"s bed and the lake, and within four or five miles of the lake. This information I get through a letter written from Cle-ellum to Mr. Whitworth. I have no personal knowledge of these Cle-ellum beds.
[Sidenote: Undoubtedly large beds of steel ores.]
There can be no doubt as to the existence in the Cascade Mountains along this line of superior iron ore in large quant.i.ties, the most of which is suited to the manufacture of steel.
[Sidenote: Of superior quality.]
There can be no doubt as to the superior quality of the Snoqualmie iron ores. a.n.a.lysis shows that they rank with the best steel ores in their large percentage of metallic iron and small admixture of deleterious impurities. Of the following tables, the first gives all the reliable a.n.a.lyses I could obtain of the ores of the Snoqualmie region of the Cascade Mountains. Those reported from Mr. Kirke and Mr. Dewey are of high authority. Those from Mr. Jenner are given in Governor Squire"s report for 1885, and are probably equally reliable.
a.n.a.lYSES OF SNOQUALMIE IRON ORES.
----------+---------------+----------+----------+----------+----------- Kind.Locality.Silica.MetallicSulphur.Phosphorus.
Iron.----------+---------------+----------+----------+----------+-----------{Summit.1.3071.17.00-1/2.04Mt. { "2.7368.56.02.03-1/2}[1]
Magnet.i.te.Logan { "2.2369.40.00-3/4.03-1/2}{ "1.8770.18.01-1/4.03 } [2]
{ "1.6767.000.050.02 }+----------+----------+----------+-----------Average1.9669.26-1/5.01-9/16.03-1/5 BogIronstone.{9.3745.50Traces0.08 }Middle{6.0364.500.05---- } [2]
Micaceous.Fork {22.3259.500.05Trace }(Guye).{3.3367.800.03Trace } Hemat.i.te.{11.7760.900.02Trace }{ No. 12.7269.390.0420.035Denny { No. 21.3071.170.0050.039 [3]
Magnet.i.te.Mt. { No. 32.7368.560.0190.035{ No. 44.0267.170.0410.031{ No. 52.2369.400.0080.035{ No. 61.8770.180.0130.031+----------+----------+----------+-----------Average2.47-5/869.31-1/60.021-1/30.034-1/3 ----------+---------------+----------+----------+----------+----------- Authorities: 1. Dewey (chemist).
2. Reported by Kirke.
3. Reported by Chas. K. Jenner, from a Philadephia chemist.
[Sidenote: Proved by a.n.a.lysis to be unsurpa.s.sed, if equaled.]
By way of comparison, I next introduce a table of a.n.a.lyses, which begins with what Mr. Phineas Barnes, in his report on the steel industry of the United States (1885), gives as a typical steel ore from the best American mines. The second a.n.a.lysis gives the average of fourteen a.n.a.lyses of the best Lake Superior steel ores. The third is a typical steel ore from the Iron Mountain of Missouri. The fourth is the average of all the a.n.a.lyses of the magnetic ores of the Snoqualmie Valley, which name I give to them to distinguish them from similar ores on the east side of the Cascade Mountains, of which I have no a.n.a.lyses:
COMPARATIVE a.n.a.lYSES OF STEEL ORES.
------------------+--------------+---------+-----------+-----------Metallic Iron.Sulphur.Phosphorus.Silica.
------------------+--------------+---------+-----------+----------- Typical Steel Ore59.24-2/3.20-2/3.03-2/36.17-2/3 Lake Superior68.48----.0532.07 Iron Mountain65.500.016.0405.750 Snoqualmie68.80-8/13.023-4/13.028-2/32.61-10/13 ------------------+--------------+---------+-----------+-----------
This showing places the Snoqualmie ores in the front rank of American steel ores; indeed, it shows a little higher in metallic iron, and a little lower in phosphorus, than any of the others. These a.n.a.lyses are, of course, made from the ore proper; _i.e._, without any addition of the matrix, or gangue-rock, in which the ores are imbedded. With all magnet.i.tes of this type it is only in exceptional spots that much of the ore can be gotten, free from the enclosing rock. Under ordinary circ.u.mstances something like 20 per cent. of the ore sent to the furnace will be gangue-rock. There is reason to hope, however, that ere long there will be a practical method for separating the rock from the ore, and at the same time getting rid of most of the sulphur. At Cranberry, N. C., the ore is now roasted and stamped into small bits, and an experiment has been made of pa.s.sing the ore through a jigger, whereby the hornblendic and other enclosing rocks were separated by the pulsations of the water, as in coal washing.
[Sidenote: Improved processes.]
The Lackawanna Iron and Coal Company, Pennsylvania, has been separating the ore from the rock with good results. The same has been done at Crown Point, N. Y., Lion Mountain, near Plattsburg, N. Y., Negaunee, Mich., and Beach Glen, N. J.
The process is really one of concentration, in some respects similar to that pursued with the refractory ores of the precious and base metals.
The ore is first calcined sufficiently to make it friable. It is then crushed, by a Blake or other rock-breaker, and is finally sluiced, or jigged, or both. The aim is to produce a Bessemer concentrate which would yield 60 per cent. or more metallic iron, and at the same time get rid of whatever phosphorus might be in the gangue-rock. In the best experiments the object was more than accomplished. The concentrate contained 63 per cent. of metallic iron, the middlings 55 per cent., and the tailings 16 per cent. This experiment was made with a refractory Adirondack magnet.i.te, which was so intermixed with hornblende, quartz, mica, etc., that the ore might be described as a hornblendic gneiss, carrying a large proportion of magnet.i.te. No doubt experience will teach some way of saving the ore that is now wasted in the tailings.
Thus we may hope to see removed in a short time the only practical difficulty in working the crystalline magnet.i.tes, such as those of Snoqualmie, and many others.
[Sidenote: Granite.]
III. GRANITE, LIMESTONE AND MARBLE.--What is here called granite is really syenite. It is found high on the mountains, a.s.sociated, as already intimated, with the magnetic iron ore, and with hard quartzite, porphyry, epidote, hornblende, and limestone largely marbleized. This group of rocks forms the core of the Cascade Mountains, and hence underlies all the coal-bearing rocks to the westward. The group has been a.s.signed by some geologists to the Archaean age; but it is possible that they are metamorphosed strata of the Silurian, or some subsequent period. Some of this syenite has a large proportion of quartz, which gives it a light appearance; but in other places the hornblende crystals are of good size and in full proportion, and the feldspar is of the orthoclase variety, which gives a mixture of three colors, and makes fully as handsome a stone as the Quincy granite.
Limestone is reported as existing in some of the islands in Puget Sound, where it is burnt into lime; but I have met with no particular account of it.
[Sidenote: Marble and limestone.]
The limestone and marble a.s.sociated with the iron ore on the Cascade Mountains has already been alluded to. It is of fine quality, very abundant, and easily quarried. It will have great value for flux and commercial lime. It is also beautiful in color, varying from the purest white to blue, and mixtures of the two colors. In texture it is sometimes exceedingly fine grained, and in others crystallized into a true and beautiful marble, which, so far as can be judged by eye, would be well adapted to both inside and outside finishing and statuary. On Mount Logan the limestone deposit almost covers the mountain above the lower line of the iron ore, and is so exposed as to be quarried with the greatest ease.
The same a.s.sociation of limestone in heavy beds with iron ore seems to exist also on the Cle-ellum, as mentioned by Mr. Burch. This gentleman spoke to me, also, of a very beautiful and easily burned limestone in the Wenatchie Valley. Large beds of limestone also exist in connection with the precious and base metals, which are next to be described. In the Colville country limestone seems to abound.
[Sidenote: Precious metals on Cascade Mountains.]
IV. THE PRECIOUS AND BASE METALS.--In the Cascade Mountains, and in the mountains north of the plateau country of East Washington, and in the Coeur d"Alene Mountains, within the border of Idaho, occur numerous veins bearing gold, silver, copper, lead, sulphur and iron. Discoveries on Cascade Mountain proper have been made on both sides, chiefly in the region of the iron ore. Those at the Denny and Chair Peak mines have been most spoken of. Professor Mason, of the "Rennselaer Polytechnic Inst.i.tute," Troy, New York, gives the following a.s.say of two samples sent from the Chair Peak claim of Kelly, Wilson & Co.:
1st. Silver 13.9 oz. per ton.
2d. Silver 12.4 Both 14% copper.
Professor Price, of San Francisco, also a.s.sayed a sample from the same vein.
Silver $3.63 per ton.
[Sidenote: On Cle-ellum River.]
Metallic veins are found also in connection with iron ore on Cle-ellum River. Mr. Burch reports a copper and silver lode, and also two lodes of gold and silver, in this neighborhood. He reports the ores as high grade, of good, workable thickness, and outcropping for several thousand feet. There is a gray ore in the same region, the character of which has not yet been determined. This has already been mentioned as lying close to the iron ore, and may possibly be metamorphosed chalcopyrite. Mr.
Burch thinks that the silver ores will run from forty to eighty ounces, while in some spots the richness is very extraordinary. The lead ore in a.s.sociation ranges from fifteen to forty per cent.