(This is from the January 6, 1906, edition of The Engineering And Mining Journal, pp. 26-29.)
Mining of Zinc, Lead, Iron, and Coal in Virginia
BY THOMAS L. WATSON*
The varied mineral wealth of Virginia has long been known. The wide and varied range of this mineral industry is indicated by the fact that more than 24 different minerals are produced on a commercial basis. To this may be added a dozen or more known minerals which occur in the State but are not yet produced on a commercial basis. According to a special report of the Census Office on “Mines and Quarries” for 1902, “the total value of the products of the manufacturing industries based upon mining was $27,272,601, or 20.6% of the total value of the product of all manufacturing industries in the State in 1900.” This variety makes the mineral industry an important factor in the commercial activity of the State. The present paper reviews briefly the principal producing areas of zinc, lead, iron and coal in the State, with special emphasis on the more important recent developments in these respective areas.
Zinc and Lead.—The workable deposits of lead and zinc ores in Virginia, as a rule, are intimately associated. Lead mining in the State dates back more than 150 years; but the production of zinc ores is much more recent, commencing with the opening of Bertha mines, in Wythe county, in 1879. Practically the entire production of the Virginia mines from the beginning in 1879 to the present time (Sept, 1905) consisted of the soft ores, carbonate and silicate, largely the latter, which assays about 40% metallic zinc. In 1893 the Bertha mine alone was producing 200 tons of soft ore per day. Since 1898, however, these mines have been worked for iron ore only, the zinc ore having been practically exhausted. The closing down of the Bertha mine as a producer of zinc ores has been followed by a decrease in production of zinc ores in Virginia. This condition has been productive, however, of a search more systematic than formerly for new deposits of zinc ores over the Virginia region; and, at present, much prospecting is in progress over parts of southwest Virginia.
Recent exploitation in this district has not been in vain; while development work has not been carried far in some places, it has in others, and it is believed that the future production will equal that of former years. The production in the future, however, will be of sulphide ores; and not, as in the past, of soft ores, silicate and carbonate. The outlook is especially encouraging at Austinville, where large well-defined ore shoots of the sulphides are being developed. Prospecting is in progress in the southwest corner of Wythe county, at Cedar Springs; and at Rye Valley, Smith county, to miles west of Cedar Springs. Conditions are encouraging at both places, but particularly so at Cedar Springs, where a very pure massive blende has been opened, which should prove to be an easy milling proposition. The Cedar Springs Zinc Mining & Development Co. contemplates the erection of a commodious and modern concentrating mill at the mines at an early date, when systematic mining of the ores will begin.
Exclusive of the places mentioned above, there are many points in the Virginia district where prospecting is in progress, but the work has not reached the stage where a definite statement can be made. It is of interest to note, however, that prospecting is being so vigorously carried on in so many places.
Probably the most important advance made in the Virginia zinc industry during the year 1905 was a scheme for the utilization of low-grade zinc ore and washer tailing, which formerly were not considered workable. In accordance with this, a zinc-oxide plant, consisting of 12 furnaces, was recently built at the Austinville mines, in Wythe county. The grade of zinc ore, including tailing, used for making the oxide will average at Austinville from 15 to 20% metallic zinc. The plant has proved satisfactory. The oxide made at Austinville is shipped to the furnaces at Pulaski, where it is used for making spelter. As made at Austinville, the oxide contains about 4% metallic lead, and will average 70 to 75% metallic zinc. The successful operation of this plant at Austinville is of considerable importance, since it points out a method for utilizing low-grade zinc ores which elsewhere are not profitable.
Extensive improvements and developments were in progress during the past year at the Albemarle Zinc & Lead Co.’s mine in Albemarle county. A concentrating mill of 80-ton capacity per 24 hr. has just been completed, including eight sets of jigs, crushers, rolls and screens; also steam of sufficient power for operating the entire plant, with hoist, tram-cars and cable, for conveying the ore from the shaft to the mill. The dry process is employed here for separating the ore, which differs from the wet process only in the form of the jig used. The Crum jig is used at this plant, which substitutes air for water; the jigs can be set to 700 puffs of air per min. Compressed-air drills have recently been added to the underground mining outfit.
Iron Ores.—In value of production, iron ranks as the second mineral in the State, being exceeded only by that of coal. The total State production of iron ore per year is approximately 800,000 long tons, valued at the mines at about $1,500,000. Three types of ores are produced, proportioned in output about as follows: brown hematite or limonitic ores, 765,000 long tons; red hematite, including red fossil ore, 32,000 long tons; and magnetite, 4,500 long tons. The production of brown iron ores of Virginia forms an important percentage of the total output in these ores in the United States. Until recently Virginia held first rank among the brown ore-producing States, and at present it is exceeded in production only by Alabama.
Virginia is conveniently divided into four principal iron-producing areas as follows: (1) the Oriskany, which includes the counties of Alleghany, Botetourt and Craig; (2) the limestone area of southwest Virginia, which includes the counties of Pulaski, Wythe and Smyth (forming the New river-Cripple creek division) and Roanoke and Washington counties: (3) the Clinton, which includes Wise and Lee counties; and (4) the Piedmont or crystalline area, which includes Pittsylvania as the chief producing county.
The Oriskany Area.—The district derives its name from the geological horizon in which the ores are mined, the Oriskany sandstone. With the exception of one mine opened in the red fossil or Clinton ore, brown hematite comprises the only type of ore mined in this district. The principal mines in operation in the area during the year 1905, were: Oriskany, Ritch Patch, Longdale, Glen Wilton, Dolly Ann, Fenwick, Reid and Low Moor, operated by the following companies: Aleghany Ore & Iron Co.; the Chapman Iron, Coal & Coke Co.; the Longdale Iron Co.; the Low Moor Iron Co., and the Princess Iron Co.
A total of nine furnaces using Oriskany ores were in blast in 1905, distributed as follows: The Alleghany furnace at Iron Gate, the Buena Vista furnace, at Buena Vista, and the Gem furnace at Shenandoah. These three furnaces are owned and operated by the Alleghany Ore & Iron Co. The Longdale furnaces Nos. 1 and 2, operated alternatively, are owned by the Longdale Iron Co. The Victoria furnace is owned by the Chapman Iron, Coal & Coke Co., and is located at Goshen. The Low Moor Iron Co.’s two furnaces, alternate stacks, are at Low Moor. The Princess furnace, at Glen Wilton, is owned by the Princess Iron Co. The Liberty furnace, at Liberty Furnace, Shenandoah county, owned by the Monarch Blast Furnace Co., is located north of the Oriskany area and runs on local ore. Of these furnaces the Buena Vista and Longdale Nos. 1 and 2 make basic iron; the remaining ones make foundry and forge iron.
The Oriskany is the largest mine in Virginia; it is producing at present at the rate of 100,000 tons of ore per year. It has large ore reserves, and the company is preparing to instal a new washer.
At Low Moor, operations have been shifted from the mining of brown ores of the Oriskany, to that of red fossil ore of the Clinton. This is the only known locality in Virginia where the Clinton red fossil ore is mined outside of the area of Lee and Wise counties. Clinton ore, however, has been mined in a number of places in this vicinity in former times; it is believed that this marks the beginning of renewed activity in the mining of Clinton ore in this locality. This property was opened up during the past year and shipment of ore was begun. It is now producing at the rate of 50 tons of ore per day. The opening from which the ore is mined was made near the crest of an anticlinal fold, breached on one side and exposing the ore bed, 760 ft. above the valley bottom. The ore is handled by a gravity system of cars, so that the loaded cars in descending to the tipple force the empty cars up the incline, 1,800 ft. long, to the mine openings. As yet the ore has been mined only along the crest of the anticline. Where mined, the ore-bed has a thickness of 28 in., the ore averages 47% metallic iron. It is underlaid by soft shale, a condition utilized for driving car-headings. At the Ritch Patch mine the ore is won at present by underground workings, chiefly from the head of tunnels driven into the orebodies; this is preparatory to the opening up of robbing-rooms, the usual method of winning the ore. At the surface workings of this mine considerable stripping is in progress, preparatory to the continuation of steam-shovel work.
In the Australia mine of the Longdale Iron Co., electric power has recently been installed for driving the ventilating fan. A compressed-air device has also recently been installed for handling the loaded cars at the shaft.
Near the Daggers Springs mine, in Botetourt county, recent prospecting has developed a promising body of Oriskany ore. Two openings are made from which ore is mined at present. As fast as mined the ore is stored on the grounds awaiting transportation facilities.
The Limestone Area of Southwest Virginia.—The limits of this area have been already given. Brown hematite comprises the only type of ore mined, confined almost entirely to the Shenandoah limestone of Cambro-Ordovician age; but the ore is associated in places with the underlying quartzite where the overlying limestone has been stripped by weathering.
The principal mines in operation in this area in 1905 were: The Faris, Rich Hill, Reed Island, Hurst, Patterson, Crawford, Tipton, Barron Springs, Red Hill, Sanders, Bertha, Foster Falls, Hematite, Little Wythe, Norma, Clayton, Locust Hill, and Taylor’s Valley; these are operated by the Virginia Iron, Coal & Coke Co., and the Pulaski Iron Co. In addition to these, there are a few private operators in the district, but the region is practically controlled by the two companies named above.
The furnaces in blast in this area during 1905 were: The Pulaski furnace, at Pulaski, owned and operated by the Pulaski Iron Co.; the Bristol furnace, at Bristol; the Max Meadows furnace, at Max Meadows; the Radford-Crane furnace, at Radford; the Reed Island cold-blast charcoal furnace, at Kayoula; the Dora furnace, at Pulaski; and the Crozier furnaces No. 1 and 2, at Roanoke; all of which are owned and operated by the Virginia Iron, Coal & Coke Co. The West End furnace, at Roanoke, is operated by the West End Furnace Company.
The Faris mine, recently opened up near Allisonia, Pulaski county, is reported to have produced 30,000 tons of ore in 1904. During 1905 a second steam-shovel was added to the mining outfit.
The Clayton mines, located on Draper mountain, near Pulaski, were opened up by the Pulaski Iron Co. during the year 1905. A narrow-gauge railway has been constructed to the mines by the company, and ore is being shipped. The same company has also recently opened up a valuable mine, called the Norma, near Cripple creek, in Wythe county. Brown lump ore is being shipped at present and a railway to the mines is under construction. A continuation of the Cripple Creek extension of the Norfolk & Western railway from Cripple creek to Speedwell has opened up another section of this famous valley.
The Ganaway, Andis and Speedwell banks, located near Speedwell and owned by the Virginia Iron, Coal & Co., will be producing at an early date. Some activity is being shown by this company in establishing new washers at old mines in several places over the Cripple creek region. In Rye Valley, Smyth county, considerable recent prospecting was in progress in connection with the completion of the Marion & Rye Valley railroad to Sugar Grove. Mining on rather a small scale was in progress during 1905 on Slemp’s creek; the ore was hauled in wagons to, and shipped from, Sugar Grove.
Near Brown’s Siding, on the Virginia Carolina railway, in Washington county, a rather unique association of ore (including brown hematite, magnetic hematite, and ferruginous limestone) was partially developed during the past year. Some ferruginous limestone was shipped which averaged 30% metallic iron and was self fluxing.
In Taylor’s Valley, at the Virginia Tennessee line on the Virginia-Carolina railway, a property of brown hematite ore which promises well is being developed. A railway has been built to the mines and the mine has begun producing. Across the line in Tennessee, near Laurel Bloomery, the Ward mine has been opened and a washer built. A narrow-gauge road has been completed between the mine and Damascus, connecting at the latter place with the Virginia-Carolina railway. This mine began producing September, 1905; the output is now said to be 2,000 tons of ore per month.
Lee and Wise Counties.—In this area the Clinton red fossil ore is being mined from two beds, having a thickness of about 3 ft. each, and averaging 40% metallic iron. The Keystone Coal & Iron Co. is operating at Oreton, Wise county. Kelly & Irvine are operating at Big Stone Gap. The Boone Path Iron Co. is operating in Lee county. The Union Furnace at Big Stone Gap, Wise county, is owned and operated by the Union Iron & Steel Company.
The Piedmont Area.—The operations in this area are small and scattered. The principal producing county is Pittsylvania. The ores mined in the Piedmont area include red hematite and magnetite.
Furnaces Recently Operated but Now out of Blast.—These are: The Graham furnace, at Graham, operated by the Graham Iron Co., Lessee; the Ivanhoe furnace, at Ivanhoe, Wythe county, owned and operated by the New River Mineral Co.; the White Rock warm-blast charcoal furnace, near Rural Retreat, Smyth county, owned by the Lobdell Car-Wheel Co.; the Foster Falls warm-blast charcoal furnace, at Foster Falls, owned by the Virginia Iron, Coal & Coke Co.; and the Covington furnace, at Covington, owned by the Low Moor Iron Company.
The Foster Falls, Red Island, White Rock, and Liberty furnaces are the only charcoal furnaces in the State; all the others are modern coke furnaces.
The only furnaces making basic iron in Virginia are the Longdale and Buena Vista; the remaining ones make foundry, forge, and car-wheel iron. The reason for this is seemingly due to a difference in the composition of the ores in the two principal producing districts, namely, the Oriskany and the Limestone area of southwest Virginia, especially as regards the manganese content; the Oriskany ores, as a rule, contain higher manganese than the limestone ores.
Preparation of the Ores.—All the brown ores mined in the State are washed in order to remove the admixed clay. The ores are washed in log washers. In some instances, associated sand with the ores necessitates subsequent jigging. In the limestone ores of southwest Virginia, the ores are admixed principally with clay and have little associated sand; while in the Oriskany ores, there is relatively less clay and more sand. For this reason the Oriskany ores require jigging, whereas no jigging is usually required of the limestone ores in southwest Virginia.
Coal.—The annual production of coal in Virginia is about 3,500,000 short tons, valued at, approximately, $3,500,000. The first production of bituminous coal in the United States was reported from the Richmond basin in Virginia early in the last century. The rank taken by Virginia as a coal-producing State, however, may be said to properly date from the opening up of the famous Pocahontas district in 1882.
The coal deposits of Virginia may be grouped into three principal districts: (1) The Richmond Basin; (2) the area of Montgomery and Pulaski counties; and (3) the Southwest Area, which forms the southeastern part of the Kanawha basin.
The Richmond Basin.—The Richmond area lies within and near the eastern margin of the Piedmont plateau, on either side of the James river; it covers the counties of Henrico, Chesterfield and Goochland, and parts of Powhatan and Amelia. It comprises a total area of about 190 sq. mi. The strata consists of thick shale and sandstone, and scanty conglomerate, of Jura-Trias age.
This area is important, economically as well as scientifically; it contains the only free-burning coal located immediately adjacent to tidewater in the eastern portion of the United States. It is historically important, since it furnished the first production of bituminous coal mined in the United States. The production from the Richmond Basin increased from 54,000 tons in 1822 to more than 100,000 tons in 1828; during each of the years from 1822 to 1828, inclusive, the output from the district is reported to have exceeded that of Pennsylvania anthracite. The production front the Richmond Basin is reported to have increased continuously until 1832, when it began to decline; by 1850 it had almost ceased.
While the production from the area for many years has been small, it by no means follows that the coal has been exhausted; a detailed geologic study of the ores by Shaler and Woodworth indicates the presence of a quantity of coal sufficient to give the area much value. As proved by nearly a century of constant use, the quality of the coal is satisfactory for many purposes.
Additional importance attaches to the areas because of the occurrence of natural coke, which has long been in use; it stands high in the neighboring towns as a domestic fuel.
Operations in this area during 1905 were confined to Winterpock and Midlothian, in Chesterfield county, largely development preparatory to shipping. The Gaylor mines, north of the James river, in Henrico county, were closed down several, years ago. Since closing down, the mines have changed hands, but as yet work has not been resumed. At Winterpock, a new incline was under way during the summer of 1905. At Midlothian, development work was in progress during 1905; the only mining of coal was limited to that for the company’s use. The developments at Midlothian comprise a new incline, 1,020 ft. long by 16 ft. wide and 7 ft. high, on a 33° pitch. The year 1906 will be consumed in the completion of development work preparatory to shipping.
Montgomery-Pulaski Area.—This lies 30 to 50 miles west of the city of Roanoke. In the Montgomery county portion of the area, the mines are opened along the south slope of Brush mountain and on the two slopes of a diminutive parallel ridge, locally known as Prince mountain, distant about 6 miles south from Brush mountain. In Pulaski county, developments have been on the slopes of Cloyd and Little Walker mountains, which are a southwest continuation of Brush mountain in Montgomery county. The coal area lies near the northern border of the two counties, and is crossed by New river, which is the dividing line between the counties.
The total estimated acreage of the Montgomery portion of the field is about 7,000 acres. The extent of the Pulaski part of the field is not certain, but it is probably nearly equal to the Montgomery field. It extends from New river to the town of Pulaski, which includes the developments so far made.
Coal was mined in this field prior to the Civil War, but not in an extensive way. It is reported that some of the coal used in the bunkers of the Merrimac (Virginia), in her fight with the Monitor in Hampton Roads, came from the Price mountain mines. For a period of 30 years after the Civil War the only mining carried on in this field was to supply a local market. For a number of years past large developments have been made, more extensive and systematic mining has been carried on in accordance with modern methods, and a steady increase in output over that of the local market has been indicated yearly.
The coal seams occur in strata of Mississippian or Lower Carboniferous age. On Price mountain, five coal seams are indicated, only one of which has yet proved to be workable. An average thickness of 4½ ft. of clean coal is mined from this seam. On Brush mountain, two seams yield workable coal, which average in thickness 3 and 4½ ft. of clean coal, respectively; they are named the “Little” and “Big” seam. Likewise two seams are worked in the Pulaski portion of the field. The coal is of excellent quality, of the semi-anthracite type. That of the Price mountain mines is harder, and consequently not so free-burning as the coal from Brush mountain.
In 1905 more than a half-dozen mines, operated by as many different companies and private parties, were in active operation on the north and south slopes of Price mountain. The product of these mines is in great demand as hard coal. The Virginia Anthracite Coal Co. has acquired most of the mineable coal property in Montgomery county. In the fall of 1904, a standard-gauge steam road was completed from the Norfolk & Western railway at Christiansburg to Blacksburg, via the Merrimac mines on Price mountain. The Virginia Anthracite Coal Co. has recently complded a breaker at the Merrimac mines, having a capacity of 500 tons per day with the present machinery; but by installing duplicate screens and other machinery, this capacity can be more than doubled. The breaker has a storage capacity of 500 tons. The average run of the breaker at present is 100 cars of coal per month. The depth of working at these mines is 1,026 ft. on a dip of 22 degrees.
Underground work at the Merrimac mines is being pushed rapidly. As soon as sufficient ground is opened, additional machinery will be installed, and the breaker will be raised to its maximum capacity of 1,000 tons per day. Work is going forward on a large scale; agencies have been established in Chicago, Cincinnati, St. Louis, Roanoke and Richmond, where the Virginia product sells in competition with that from Pennsylvania.
During 1905, some half dozen operators were actively engaged in mining coal in the Brush mountain area; the principal ones being the Virginia Anthracite Coal Co., the Blacksburg Mining & Manufacturing Co., and a number of private individuals.
The principal mines working in the Pulaski field during 1905 were the Altoona, Belle Hampton, and the Kimball. The Kimball mines are located on New river, where it is crossed by the Norfolk & Western railway. This property has recently been acquired by the Pulaski Anthracite Coal Co., which is making extensive improvements, and which has a promising outlook. A breaker has recently been erected at these mines, and a small one is being built at the Belle Hampton mine by the Belle Hampton Coal Co. The Altoona mines, located 6 miles northwest of Pulaski, are owned and operated by the Bertha Mineral Co., at Pulaski. All the coal formerly used by the Bertha company at its zinc furnaces in Pulaski came from the Altoona mines, but only the “firing” coal or reducing material is obtained there at present.
The Southwest Virginia Coal Area.—This is much the largest, most productive and most important coal area in the State; it is probably the most valuable occurrence of bituminous coal found in the United States. In fact, it is due to this area that Virginia is entitled to rank among the coal-producing States. Of the total output in coal from the State last year, the southwest area produced more than 3,250,000 tons, valued at $3,225,000.
This area is located in the extreme southwestern part of the State; it forms the southeastern portion of the Kanawha basin, and comprises the following counties: Tazewell, Russell, Scott, Buchanan, Wise and Lee. Of these, Wise and Tazewell counties are the important producers, with reported large reserves undergoing prospecting in places in the other counties. The relative importance in production of Wise and Tazewell counties is indicated in the following published returns from the two counties: Wise county produced in 1903, 2,563,285 short tons of coal, valued at $2,322,855; Tazewell county for the same year produced 840,195 short tons, valued at $883,289.
The construction of the Norfolk & Western railway through southwest Virginia in 1882 opened up the famous Pocahontas coal district, which comprises Tazewell and Buchanan counties, in Virginia, and McDowell, Wyoming and Mercer counties, in West Virginia. The district includes about 450 sq. mi. of rough, mountainous land. The first mine is said to have been opened in 1882 at the village of Pocahontas, in Tazewell county, Virginia, from which the area derived its name. The principal vein worked in the district is the great Pocanhontas vein No. 3, which is 11 ft. 3 in. thick. The method of mining employed is the “double-entry system,” with rooms driven opposite each other and at right angles to the main entries. Ventilating fans of 300,000 to 500,000 cu. ft. of air per minute are used, and are driven either by steam or by electric motors. Tracks are laid in the rooms from the main entries, and the cars are hauled out by either electric or steam locomotives.
The Pocahontas coal has long been recognized as one of the best steam coals in the world. This is based on its low percentage of ash, volatile matter and sulphur and its high fixed carbon.
The Wise county area is usually referred to as the “Big Stone Gap coalfield”; it has an approximate area of 540 sq. mi. in Virginia and Kentucky.
Although the largest coal- and coke-producing county in the State, Wise was the last to be developed. Building of the Clinch Valley division of the Norfolk & Western railway in 1891 marked the beginning of the development of the Wise county coal district. Approximately 3,500 coke-ovens are operateci in the district, which produce about 80% of the Virginia coke output.
The workable seams of coal range from 3½ to 12 ft. in thickness, of which there are eight, included within a vertical distance of about 1,200 ft. The four highest of these seams have their greatest development in the western part of the district. The Imboden, which varies considerably in thickness. is the most important seam in the area. The method of mining employed is the room-and-pillar system, with underground haulage by mules and electric locomotives. Ventilating furnaces are in use at many of the mines; exhaust fans are used as the mines become more extensively worked.
*Geologist in charge. Geological Survey of Virginia.