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parallel to the vein, but dipping in an opposite direction (400-750 northwest). They cross the vein at the pinches in the ore body, and thus tend to emphasize its shootlike character. In all cases observed the downthrow occurred on the foot-wall side of the faults to the extent of from 5 feet to 35 feet.
As mining progressed several additional faults were observed, at which the throw of the ore body was found to be greater than in any of the instances described above, but their exact positions and the magnitudes of their throws are not known. In 1891 a fault in the bottom of the mine threw the ore body to the right, but upon sinking 40 feet it was recovered with its normal thickness. With increasing depth, however, the ore became bunchy, so that it no longer paid to work. At the southwest end of the mine a drift was started at a depth of 600 feet and driven southwestward 800 feet, when another well-developed fault was encountered, that threw the vein to the left a distance of 70 feet. This fault comes to the surface at the base of the hill 1,000 feet east of the highway. On the southwest side of the fault the deposit opened to a width of 15 feet to 20 feet, and this was tested for a distance of 500 feet. It continued to be rich in iron, but the phosphorus in it was so high that the ore had to be sold at a price that was unprofitable. The deposit was supposed to be the same as that of the Orchard mine. Since it could be worked much more cheaply through the Orchard shaft, it was thought best to close down the mine, which was done in 1896.
The ore was a mixture of magnetite, calcite, quartz, chalcopyrite, apatite, siderite, pyrite and zircon. The calcite was in veinlets and incrustations on the walls of fissures in the wall rocks. The siderite was in seams and bunches in quartz, and also formed a matrix cementing masses of granular magnetite and quartz. The apatite often occurred in masses 6 inches in diameter, that were apparently crystals, in an aggregate composed of this mineral, quartz and magnetite. The quartz, besides being found in the wall rocks, occurred also as lenses in the ore, and in these were found "bunches" of chalcopyrite.
Analyses of the ore taken from the various slopes in 1867 give ideas of the quality of the ore at that time. The results are as follows (N. J. 1868, p. 582):
Northeast stopes 69.2 1.0
Northeast stopes of southwest workings, 64.7 1.1
Middle stopes at northeast fault, southwest workings, 65.5 0.3
Center of deposit, southwest end, southwest workings, 69.6 0.1
Southwest stopes 07.0 -1.6
A sample of 10 carloads mined in 1880 from the northeast working gave:
Fe = 64.85; P = .185. Authority: 10th Census, p. 171. The ore of the Teabo vein in 1886 is reported as containing: ^=66.0; P=.1o6.
References: N. J. 1855, pp. 201-206; 1868, pp. 578-582; 1873, p. 44; 1879, p. 55; 1880, p. 107; 10th Census, pp. 170-171; 1883, pp. 107-109; 1884, pp. 86-87; 1885, pp. 100-101; 1886, p. 148; 1890, p. 61; 1891, p. 245; 1896, pp. 327-328.
(251) The Baker Mine.
The Baker mine, in Rockaway Township, Morris County (northeast Baker), adjoins the Mt. Pleasant mine on the north.
It was opened in 1866 on two veins of ore 300 feet apart, of which the western one was 7 feet thick and the eastern one 23 feet. In 1868 the mine was producing at the rate of 12,000 tons annually.
It was extensively developed during the next five years, and in 1873 was 325 deep and 335 feet long. The extent of the workings in 1872 are shown in Figure 23. In 1873 a new shaft was sunk southwest of the old workings, near the turnpike, east of the Mt. Pleasant mine, on the strike of the southeast vein. A third vein was opened about this time 25 feet west of the "main northwest vein," but it was small in comparison with the other two. The mine was worked continuously until 1877, yielding about 150,000 tons of ore, when the vein pinched out at the bottom. As borings of 100 feet downward in the plane of the dip of the vein failed to disclose a new ore body, the mine was abandoned. It was reopened in 1884 and worked continuously until 1890, and then again closed. In the fall of 1905 the mine was again unwatered, and a small quantity of ore was raised, but in January of the succeeding year the entire workings collapsed, burying 20,000 tons of ore that was in sight ready for removal. The accident was reported to be due to the robbing of the pillars.
References: N. J. 1868, p. 583; 1873, p. 44-45; 1879, p. 55: 1890, p. 61; Eng. & Min. Journal, Jan. 20, 1906: N. J. 1905, pp. 318-319.
(253) The Richard Mine.
The Richard mine is northeast of the Baker mine, in Rockaway Township, Morris County. It is one of the most important mines in the State, and one of the few that are still active.
The mine was first worked before 1856, and it has been in practically constant operation ever since. Between July 1. 1856, and June 30, 1900, its total production was 1,844,769 tons. Since the latter date approximately 1,000,000 tons have been raised, making the total yield to the present time amount to about 3,000,000 tons.
In 1880 ore was being taken through three shafts, of which one (No. 7), 160 feet deep, was the southwesternmost one and was near the Baker mine. The next to the northeast was No. 6, 375 feet deep, and the third (No. 3), which was about 500 feet still further northeast, was 400 feet deep. In 1883 the three shafts that were active were: No. 1, which was to the southwest of No. 7 on the vein that was supposed to be the continuation of the Baker vein. About 1,000 feet northeast of this was shaft No. 2, and 700 feet further northeast was shaft No. 3.
Five veins cross the Richard property. The three to the southeast are continuations of the Baker veins. The next to the northwest was thought to be the continuation of the Mt. Pleasant vein, and the fifth, the northwesternmost, was originally regarded as the Teabo vein.
The southeasternmost vein is the largest. This was opened up for a distance of 2,700 feet, and from it nearly all the ore came in the earlier years of the mine's history. In some of its shoots it was 20 feet wide. In other places it was pinched to 12 inches. Between the two shafts referred to there was a pinch 300 feet long. Both pinches and shoots pitched northeast at low angles (about 150) and dipped 530 southeast.
During the development of this vein several faults were encountered crossing the ore body. One of these was 524 feet southwest of No. 2 shaft. This had a throw of 40-50 feet to the right, and dipped steeply to the southwest. Another, which was nearly vertical, was found 334 feet northeast of the No. 3 shaft an3 156 feet from the north line of the property. This dipped 850 northeast, and no ore has been found to the north of it, although drifts were cut across the strike of the ore vein north of the fault for a distance of 90 feet southeast and 15 feet northwest.
In 1896, at a depth of 400 feet from the surface and 80 feet east of No. 1 shaft, a 350-foot crosscut into the foot wall rediscovered the vein to the northwest, which was then recognized as the Mt. Pleasant vein. On this a new slope (No. 4) was sunk, which struck the ore at 900 feet, where it was 10 feet wide and dipped 500 southeast. Further exploration made in the foot wall of the old mine between shafts No. 1 and No. 2 proved that the supposed foot wall was only a horse of rock about 2 feet thick, and that beyond this was a deposit of ore 17 feet thick. Three drifts were driven into this (a, b and c in the cross section) and a fourth one (d) which was not completed at the time the plan was made a number of years ago. (Plate IX.).
In 1896 slope No. 3 was abandoned and a new one (No. 5) was sunk 30 feet northwest of the vein and about 450 teet northeast of No. 2, with an inclination of 520. In 1898 a new deposit was also discovered on the hanging-wall side further northeast. This, however, was thought to terminate abruptly below a bed rock. It was later explored at a further depth of 100 feet, where it was replaced by ore from 3 to 25 feet in thickness. The supposed bed rock was a fold in the foot wall. A summary of the history of the mine is given in the Annual Report of the Survey for 1904, from which the following statements are quoted (page 296-297):
''The Richard Mine contains several shoots of iron-ore, two of which are worked at the present time. No. I shoot, now referred to as the 'Mount Pleasant vein,' farthest to the north, is the one from which ore was mined in 1856. * * * Mining from this shoot continued for several years, but was then temporarily abandoned; and No. 2 shoot, now referred to as the 'Richard vein,' lying to the south and overlying the 'Mount Pleasant vein,' was opened. A cross-cut was driven in 1893 at the western end of the property, near No. 1 slope, and connection made between the 'Richard' and 'Mount Pleasant' shoots, which are about 300 feet apart. This cross-cut intersected a shoot of ore about two feet thick, lying between the 'Richard' and 'Mount Pleasant' shoots, which is referred to as the 'Middle vein.' The intersection of these shoots was at a depth of 471 feet in length on the incline. As the