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stals it is also of frequent occurrence; and in the granites, of which it forms the principal constituent in small irregular grains, it often has the crystallographic boundaries preserved.

Tungstite. As a fine yellow powder coating wolframite crystals at the Silver mines.

Illmenite.-Common in certain dike rocks; but rare in

others.

Magnetite is a common constituent of granite and diabase, in which it occurs in minute, well formed crystals of octahedral habit. It resists decomposition much longer than the other components of the crystalline rocks except quartz, and consequently is washed away with the latter. Owing to its high specific gravity it rapidly accumulates in small excavations, where the currents of water in the freshet runnels are less rapid, and forms pockets of "black sand." A part is magnetic but a considerable portion is not so, owing doubtless to the fact that it has changed to hematite or limonite. Some of it is probably titaniferous. It occurs throughout the crystalline

area.

Hematite.-Occurs abundantly in massive deposits and in veins in the porphyries and granites.

Limonite.-Abundant in residuary deposits. Also occurs

after pyrite.

Asbolite. Black earthy cobalt oxide has been obtained at several places on the Mine la Motte estate, principally at the main shafts. It was also formerly obtained at the Old Copper mines in the southwestern corner of the tract. It usually contains nickel.

Wad. The oxide of manganese occurs almost entirely in black earthy masses associated with copper and cobalt ores.

CARBONATES.

Calcite. Found abundantly filling small crevices. In lining cavities the crystallographic faces are well formed. A large series of rhombohedrons and scalenohedrons have been observed.

Dolomite.-Abundant massive, but rather rare in crystals.

Cerussite. Found at the Mine la Motte both massive and in fine clear crystals.

Malachite.-Abundant massive at the Old Copper mines on the Mine la Motte estate, and old Buckeye mines southeast of Fredericktown and elsewhere.

Azurite.-Sparingly at Buckeye mines.

PHOSPHATES AND ARSENATES.

Apatite. Only as minute crystals in the crystalline rocks. Annabergite. The hydrous nickel arsentate is reported by Leonhard from Mine la Motte as occurring in small gobular particles of an apple green color, on chalcopyrite and galenite. Plumbogummite.-Reported by Leonhard from Mine la Motte where it is found in small greenish globules, of waxy lustre, on crystals of cerussite on galena whose surface is

corroded.

SULPHATES AND TUNGSTATES.

Anglesite.-Chiefly found in the lead mines. At Mine la Motte often occurs in good clear crystals with sharp edges. Wolframite.-Said by Haworth to occur in the main vein. at Silver mines in sufficient quantities to indicate that the deposit may be of economical importance.

SILICATES.

Orthoclase. The principal feldspathic constituent of the granites. In the porphyritic facies there are large crystals. Microcline. In well bounded crystals in porphyritic

granite.

Albite. In the acid crystallines this mineral is the principal plagioclastic representative.

Bytownite. One of the leading feldspars occurring in the

diabases.

Labradorite.-An abundant constituent of the basic dike

rocks.

Biotite. In the crystallines in small plates and grains, especially at Silver mines, Syenite and Fredericktown. Sericite. Abundant at the Silver Mines.

Muscovite.-Found in vein stuffs and as a secondary pro

duct from feldspar.

Chlorite. Abundant in weathered crystallines.

Zinnwaldite.-Found in small crystals from one to ten millemeters in size, at the Silver mines.

Hornblende.-Common as a constituent in the granite south

of Syenite.

Topaz. In minute grains at the Silver mines, where it occurs in the altered granite.

Zircon.-Very abundant in minute crystals usually imbedded in feldspar crystals in granite. Sometimes forms clusters around biotite.

base.

Augite.-Abundant as an essential constituent of the dia

Olivine. Common in grains in certain diabases.

Epidote. Rather rare. In small grains, as a secondary product, from the basic dikes.

WATER AND WATER POWERS.

The waters of the district may be regarded as belonging to two classes, the surface and the mineral. With the former the area is well supplied. Two good streams with clear sparkling water flow south nearly across the sheet. Wells of moderate depth yield abundant and never failing supplies of wholesome water.

While there are a number of mineral springs in the district the best known are in the vicinity of Fredericktown. They are all chalybeate waters. One spring is situated about one mile east of the town, and at one time had a wide reputation. The other is White spring located about six miles south of Fredericktown. It is beautifully situated and with a little expense the place could be transformed into a attractive resort. The rate of flow is about sixty gallons a minute; the temper ature of the water about 52 degrees, that of the air being 72 degrees. The results of the analysis of this water by Schweitzer is as follows:

[blocks in formation]

Specific gravity=1.0004. Trace of organic matter: No K; no Li; no SO3.

[blocks in formation]

For water powers the St. Francois river has a sufficient fall and volume to supply considerable power. At the present time there is only one dam. This is at Silver mines, but is not now utilized. It is a substantial stone structure having a head

of twenty-four feet. (See plate xiv.)

SOILS.

With the exception of very limited alluvial areas the soils of the region are all residuary. They are composed of the

[graphic]

DAM ON ST. FRANCOIS RIVER AT SILVER MINES.

PLATE XIV.

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