rental and under the same working requirements if the covenants and conditions have been performed and fulfilled, and thereafter it may be renewed for successive terms of twenty years on such conditions and at such rent as the regulations may provide.

5. The person, partnership, syndicate or company to whom the mining rights may be awarded of any lands which have been located or sold under the Feee Grants and Homesteads Act, or sold for agricultural purposes, shall compensate or settle with the owner or locatee of such lands for injury or damage done or to be done to the surface rights thereof before beginning work thereon, and if the parties fail to agree upon the amount or method of compensation, the Director of the Bureau of Mines shall have power to order and prescribe the same.

6. The Lieutenant-Governor in Council shall have power to fix and determine the maximum price at which corundum taken from lands leased under these terms and conditions may be sold for use in the Dominion of Canada, whether the ore or mineral be in the natural state as raised from the mines or in any stage of treatment or manufacture.

7. The Lieutenant-Governor in Council shall also have power to require that all corundum mined from lands leased under these terms and conditions shall undergo certain processes of treatment and milling at works to be erected in the Province to prepare it for market; and may further require from time to time, as circumstances appear to warrant, that works be established in the Province for the manufacture of all useful or commercial products for which the mineral or ore is economically adapted..

8. The Commissioner of Crown Lands may receive tenders for mining lands and mining rights in the explored belt to the 15th day of September, 1898, which tenders shall be in the form of a cash bonus to be paid to the Treasury for each lot, part lot or location applied for in addition to the first year's rental; but in considering the bonus so tendered for a lot or location, preference in the selection of mineral lands may be given to parties who will undertake to conduct mining and treating operations on the largest and completest scale, and who can furnish satisfactory assurance that they possess the requisite capital for the proposed operations-including separation of the ore from its gangue, milling for abrasive uses, manufacture of abrasive goods, and the production of aluminium.

aggregate 2,000 acres) and two water powers on the York Branch of Madawaska river in the township of Dungannon. It also provides that they shall form a joint stock company for the better carrying out of the terms of the agreement, with a minimum capital of $250,000. Such a company has now been organized and chartered, with the title of The Canadian Corundum Company. The agreement further provides for an expenditure of $100,000 before 1st July, 1902, for the following purposes, viz:

1. Acquiring from the Crown the mining leases of corundum properties.

2. Stripping and development of corun. dum properties and the production of grain corundum or other materials therefrom.

3. Development of electrical or other energy necessary to furnish motive power for machinery and works.

4. Erecting within Ontario a plant with capacity sufficient to treat not less than one hundred tons of corundum-bearing rock per day, together with factory, buildings, kilns, etc., and the installation of full machinery for the production of manufactured goods from corundum, and construction of necessary roads and tramways.

For these purposes an expenditure of $25000 is required to be made before 1st July, 1900, and $50,000 before 1st January, 1901, and out of the whole of $100,000 not less than $25,000 is required to be expended for the objects enumerated in No. 4. In the event of corundum being found adapted to new uses, the lessees agree to expend such further sums as may be necessary for the full development of such uses. They also agree to expend $1,000 per year for three years for the purpose of making a series of experiments, to discover some method or methods for the production of materials of commercial value from corundum-bearing rock other than grain corundum, special attention to be given to the production of the metal aluminium, and on 1st July of each year to furnish the Government with a confidential report of progress. A bond in the sum of $5,000 has been given as security for performance of the terms of the agreement.

A

Discoveries

Syenite and

considerable area of nepheline syenite was discovered about six years ago in Dungannon township, Hastings county, by Dr. F. Adams, who described the rock briefly in his Report on the Geology of a portion of Central Ontario, and more fully in of Nepheline the American Journal of Science. 1 Corundum. In 1896 corundum was found in the same region by Mr. W. F. Ferrier, and in the following year Professor W. G. Miller was instructed by Mr. Archibald Blue, Director of the Bureau of Mines, to examine and report upon the corundum-bearing rocks. In the course of his work it was found that the corundum occurred not only in ordinary syenites, but also in nepheline syenite.2

The Deposit

In November, 1898, the present writer examined an outcrop of the latter rock for the Bureau of Mines on York in Monteagle. Branch of Madawaska river near the northeast corner of Dungannon township, or just within Monteagle, several miles from Dr. Adams' localities, and presenting a number of new and interesting features. The rock forms a ridge running nearly north and south for about 350 yards, with a width of about 20 yards, and having a well defined schistose character, so that at first sight it would be called gneiss It is light to dark gray in color, the darker layers containing much biotite, the lighter ones more nepheline and plagioclase. On much of the weathered surface numbers of small crystals of corundum stand out, having resisted weathering better than the other constituents. In hand specimens of the unweathered rock however the corundum is scarcely noticed, and the rock has quite the appearance of fresh gray gneiss, the nepheline looking like quartz. Near the southern end of the ridge an irregular dike a few feet wide crosses the gueissoid

rock, reminding one of pegmatite. It is white and consists of immense individuals of nepheline and muscovite, often several inches or even a foot long, with small patches of blue sodalite. No felspar was seen in the dike, unlike samples described by Adams, and no corundum was found in it.

Variations in the Nepheline Syenites. As usual in nepheline syenites, there is great variation from point to point in the Constituents rock, easily seen on weathered surof the Rock. faces and still more marked in thin sections. Adams finds, as essential ingredients of the outcrops near Bancroft, nepheline, plagioclase, and biotite or hornblende in small amounts; but scapolite and calcite usually occur, as well as various minor accessory minerals. Thin sections from the locality here described show more variety in constitution. All the minerals mentioned occur except hornblende, and the felspars include orthoclase and also a little microline as well as microperthite. The soda-lime felspars are generally present in much larger amounts than the potash felspars, and seem to have a wide range in composition as determined by optical means. A few have angles of extinction of 4° or 5° from the twin plane and appear to be albite, as in the rock examined by Adams; others having a very small angle are probably oligoclase, while a considerable number range from 17° to 23°, indicating labradorite. Some have broad and sharply cut twin lamellæ, others very narrow and obscure ones. All the felspars are beautifully clear and fresh as a rule, much more so than th se of the associated Laurentian gneisses and granites.

The nepheline also is generally very fres and, as mentioned by Adams, has not the color nor oily luster of eleolite, though it seldom shows crystal forms. Large individuals often contain inclusions, minute crystals of hornblende, of biotite, and long rows of

1 Geo. Surv. Can. 1892-3, part J, n. 5; Am. Jour. Sci, vol. XLVIII, July, 1894, pp. 10-18.

2 Bur. Mines, vol. vII, pp. 210-212.

tiny dots of a transparent doubly refracting mineral. Calcite inclusions sometimes occur completely enclosed in fresh looking nepheline. In one example the somewhat weathered nepheline contains crowds of slender transparent fibers or somewhat bent cords, having a little the look of apatite but with a small angle of extinction, perhaps tremolite. Occasionally decomposition products occur along fissures, having the appearance of kaolin but without any distinct structure.

Scapolite is found in about a third of the sections, sometimes almost to the exclusion of other colorless ingredients, and has the look of a primary mineral. Its anhedra meet the adjoining felspar or nepheline in a sharply defined way, with no hint of weathering in the latter minerals. Muscovite is a very common constituent of these rocks, being found in more than half of the thin sections examined, generally as large primary looking individuals, sometimes associated with biotite, though often without it. Biotite is practically the only dark mineral in the rock, hornblende not having been observed. As in the specimens examined by Adams. it is very dark in color and has a very small axial angle. Augite was found as small blue-green anhedra in one section only. Magnetite was not found, and apatite was rare.

The most interesting accessory mineral is corundum, which sometimes occurs in fairly Microscopic well formed barrel-shaped crystals Characters. half an inch in length, but is usually smaller and often forms only minute rounded grains. Its color is gray or, less often, pale bluish. Owing to the hardness of corundum it was found difficult to prepare sections rich in crystals, and only two have been studied. Under the microscope their high refractive index and greater thickness than the rest of the section cause the corundum grans to stand out sharply. They are apt to be arranged in clusters in association with muscovite, often completely enclosed in it.

Although the rock here described has a well marked schistose structure, there is nothing in its microscopic characters to suggest shearing or crushing, no mortar structure nor granulation, and seldom even undulatory extinction to hint at a state of strain.

The rock as a whole is hypidiomorphic granular, and except corundum none of its constituents show much tendency to crystalline form.

The coarse-grained dike with its individuals of nepheline half a foot wide is not easy to study in thin sections. The nepheline proves under the microscope to have been slightly fractured, very narrow fissures being filled with a rather brightly polarizing mineral, perhaps felspar. The few inclusions are much like those of the nepheline in the schistose rock, but in one section rather large portions of muscovite are enclosed. The large crystals of pale lavender muscovite have no unusual characters, except their often perfect idiomorphy as against nepheline and sodalite. The crystals are not hexagonal in cross section, but four sided, having one angle of about 60°. The basal cleavage is somewhat inclined to the prismatic edges, though a series of pyramids having a very long C axis makes it difficult to determine the angle. In thin sections cut across the cleavage this muscovite has an extinction angle of 3° to 5o.

Distinct

Rock.

If single thin sections were to be diagnosed alone four quite distinct types of rock could be described from this outcrop: a types of the nepheline-muscovite rock; a rock made up chiefly of scapolite and muscovite with a little biotite, plagioclase, and nepheline; a rock containing about equal parts of plagioclase and nepheline with some mica, and a rock consisting of orthoclase, micr cline and nepheline with some mica. There are however transitions between these varieties, and it would be unwise to split up what is so evidently a geological unit into rocks of different names when the whole is so well defined in general character, though each hand specimen shows differences from its neighbors.

sent, except the trifling quantity of calcite and apatite, contains alumina, nepheline in particular to the extent of more than 30 per cent., this oxide must occur in very large amounts. On the other hand iron oxides must be very low, since the only iron-bearing constituent is biotite.

From Lan

in Dungannon.

Specimens from Other Localities.

A specimen of nepheline syenite was obtained from Lancaster's farm, some miles southwest of the locality just decaster's farm scribed, from a small outcrop showing no schistose structure. It is coarser grained, but of the same color and general appearance as the rock from York Branch. Thin sections show however that it has been subjected to shearing forces, since there is a granulation round the larger pieces of Felspar and nepheline suggesting mortar structure. Nepheline is present in large amounts, and also a peculiar type of microperthite having long fibrous looking inclusions of one felspar in another, the main mass being in parts very finely striated (anorthoclase ?) with twin lines making an angle of about 23° with the most marked cleavage. Oligoclase and biotite occur in smaller amounts, the latter as usual very opaque. Some of its outer scales weather to a bronze-brown color, are dichroic, and have the optical axes much farther apart than in the fresh mica.

From

Peter

Specimens of a medium-grained white rock dotted with darker minerals come from a locality not visited by the writer, Methuen in in Methuen township, Peterborough borough. county, and are interesting as containing many dark brown corundum crystals having a bright bronze lustre on basal partings, as well as minute crystals of inagnetite. Thin sections of one specimen disclose chiefly plagioclase, finely striated and with a low angle of extinction from the twin plane; a little microcline, nepheline and muscovite Sections of making up the rest of the rock.

another specimen very similar in appearance contain more muscovite and a large amount of nepheline, or rather of a turbid decomposition product, confusedly scaly or fibrous, having high double refraction. The mineral seems to have parallel extinction, fuses a white readily without intumescence to glass, and gives water in the closed tube, so

that it is no doubt a uniaxial or rhombic zeolite, perhaps natrolite. The corundum is very opaque, so that only minute particles of crushed crystals can be studied satisfactorily. It contains many inclusions of two kinds, slender black needles lying parallel to one another, and brownish red strips and plates somewhat irregularly shaped and placed. The latter are probably hematite, and produce the bronze lustre seen on basal planes of the corundum. Extinction is parallel to the needle-like inclusions, and there is a rather strong dichroism, violet when the needles are parallel to the chief section of the lower nicol and reddish-brown in the opposite position. Some fragments, no doubt parallel to the basal plane, are not dichroic.

The first of the two specimens might be named a plagioclasite (anorthosite contains a more basic felspar) if taken separately, but the second does not differ from typical examples of the York Branch nepheline syenite except in the complete weathering of its nepheline, and probably both are varying forms of the same rock mass.

From

Raglan in Renfrew.

Through the kindness of the Director of the Bureau of Mines specimens of corundum rocks from Raglan township in Renfrew county, about twenty miles northeast of Dungannon, have been placed at my disposal. One is white, somewhat schistose, and much like the Methuen specimens except that it contains. biotite, and that the pale greenish corundum crystals are almost an inch in diameter and have no bronze shimmer on basal planes. Under the microscope it is found to consist mainly of plagioclase (oligoclase) and biotite, the latter pale greenish-brown, faintly dichroic and with a small axial angle. There are also a few large patches of colorless muscovite having a large axial angle. The specimen has the mineralogical composition of a diorite, though of a very unusual character; but Professor Miller states that nepheline syenite occurs close by, apparently part of the same rock mass, though not so highly corundiferous. 3

These white rocks were taken for limestone by farmers of the region, and an attempt

3 Bur. Mines Rep. 1897, p. 222.

was made to burn them for lime, of course in vain. Hand specimens, partly fused, were taken from the kiln and supposed to be nepheline-syenite,' many of them doubtless having that composition; but the one provided for microscopic examination contains no nepheline. It is evidently part of a boulder, and is schistose and pale gray to white on the surface, but mottled bright blue and white where broken. Under the microscope the rock is found to consist of scapolite, sodalite and biotite, with a very little orthoclase. The scapolite forms the greater part - of the rock, the spaces between its anhedra being filled with sodalite; the latter blue throughout when in small portions, but only on the edges when in large ones, the centre being colorless and isotropic. The boulders are said by Miller to be blue only after being burnt in the lime-kiln. The biotite is deep red-brown in color, has a high absorption and a wide axial angle, perhaps the result of heating; just as many dark biotites turn brown by weathering and have a wider angle between the optical axes. There are small quantities of an unknown mineral present, white, transparent and having a low double refraction, so as to give only dull blue or purple tints between crossed nicols. Two or three sections of it show an axial image consisting of a black cross opening out about as far as in many biotites, but without colored rings. It is optically positive.

Drift.

About eleven years ago the writer collected a considerable number of specimens of nepheline-syenite from drift boulders boulders at in the neighborhood of Cobourg, Cobourg, in Northum- which lies about so: th-southwest of berland. the localities referred to above and from fifty to a hundred miles distant from them. At that time nepheline syenite had not yet been reported from the Province.4 In a general way these specimens correspond in appearance and composition to those that have been described, though a number cf additional minerals occur in them, the more important being hornblende, augite and garnet, both of the ordinary kind and melanite, the brown variety. Only one of the specimens collected then contains corundum;

Trans. Roy. Soc. Can., 1890, pp. 14-18.

and it, though closely like the others in appearance, shows little or no nepheline and resembles in mineralogical constitution one The purof the specimens from Methuen. plish-gray corundum crystals are quite large, and thin sections show the same needlelike inclusions and dichroism as the Methuen crystals, but not the hematite plates. there is not much doubt that the Cobourg drift boulders originated in the nepheline syenite region to the northeast, they have been referred to here and may be considered in connection with the rocks previously described,

common

exhibited in Types.

Uniformity in Variety.

As

In spite of the great variations in mineralogical composition to be seen in hand speciQualities in mens, all the rocks referred to have much in common; they are white to gray in color, generally schistose, often corundiferous, and present the same general habit, so that in field work they are naturally thrown together as nepheline syenite and can be sharply distinguished from adjoining Laurentian gneisses, granites and syenites. While not all of them contain corundum in large amounts, they serve as a general guide to the discovery of the corundiferous rocks, and are so used by prospectors for that mineral. Some of the ordinary syenites of the region however contain corundum also, and the largest crystals found occur in them.

Just why the magma which has solidified into the group of rocks described above should be so versatile in regard to mineralogical composition is not easily explained; but no other rock known to the writer shows so great a variety of types within short distances as may be found in the nepheline syenites. It may be that experiments such as those of Morozewicz will give the clue to this variability, which seems to depend on the large proportion of alumina in the original magma. The corundiferous varieties of nepheline syenite represent magmas supersaturated with alumina but not saturated with silica.

5 See Review by T. A. Jaggar: Jour. Geol., 1899, vol. VII, No. 3, pp. 300, etc.