Indium Available in Commercial Quantities - ACS Publications

of the problems are to be satisfactorily solved. LITERATURE CITED. (1) Birdseye, C., Food Ind., 3, 213 (1931). (2) Birdseye, C., and Fitzgerald, G. A...
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INDUSTRIAL AND ENGINEERING CHEMISTRY

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From the above brief consideration of the problems which have been partially solved by the chemists and those on which little headway has been made, it can be seen that, although quick-freezing has progressed a long way commercially, a great deal still needs to be done by the research worker if all of the problems are to be satisfactorily solved.

(3) Kohman, E. F.. Paper presented before the Pea Section a t the (4)

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LITERATURE CITED (1) Birdseye, C., Food Ind., 3, 213 (1931). (2) Birdseye, C., and Fitzgerald, G. A., IND.ENQ. CHEM.,24, 676 (1932).

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25th Annual Convention of the Nat. Cannera Assoc., Chicago, Ill.. Januarv 25 to 29., 1932. ~ ~ Overholser, E. L.,and Cruess, w. V., Calif. Agr. Exp. Sta., Tech. Paper 7 (1923). Plank, R., Ehrenbaum. E.. and Reuter, K.. “Die Konservierunn von Fischen durch das Gefrierverfshrung,” Zentral Einkaufgesellschaft, Berlin, 1916. Taylor, H. F., Bur. Fisheries, Document 1016 (1927). Tressler, D. K., and Murray, W. T., Fishing Gaz., 49, No. 2, 24-6 (1932).

RECEIVEDApril 7, 1932. [ E N DOF SYMPOSIUM]

Indium Available in Commercial Quantities WILLIAMS. MURRAY,805 Watson Place, Utica, N. Y.

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I K E many other elements, indium was discovered several years before sources and processes of recovery made it available for commercial use. Reich and Richter (4) are accredited with having discovered this element in 1863. Because of the indigo-blue lines which are in its spectrum, it.was named “indium.” It was one of those elements which was supposed to be widely distributed in several kinds of ores, but always in minute amounts. Later a zinc ore in Germany was reported to contain as high as 0.1 per cent. So far as the writer knows, no definite and serious effort was made to find lasting sources for this metal until a careful survey of all known ores was made. Because of the success of these efforts, indium can now be made available in substantial commercial amounts.

PROPERTIES OF INDIUM The properties of this element are fairly well known. It is a white lustrous metal, very soft and ductile, and slightly

heavier than zinc; it melts a t 155” C. and is said to boil at about 1450” C. It has very great surface stability at ordinary temperatures, but oxidizes and burns a t temperatures above its melting point, especially if finely divided. Indium is supposed to be trivalent in its stable compounds. Several of these are listed in the usual references. Especial attention has been given to its halogen compounds which are quite unstable. The cyanide is reported to be insoluble in water but soluble in cyanides of other elements. There are also listed the hydroxide, oxides, sulfide, and sulfite. It is believed that little is really known about indium and its compounds; the reason for this is that there have been heretofore but small amounts available for research, and therefore little interest was shown in such work. The physical properties are very concisely stated in a paper by Westbrook (6) from which the following is taken: Atomic weieht 114.8 3 (usually); also 2 and 1 Valence 115 Melting point, C. 1450 Boiling point, C. 7 .12 Specific gravity5 L.31 ‘27;3 Specific heat, joules per gram atom Electrical resistivity: A t 20’ C., ohms 9 x 10-6 At 155’C ohms 29 X 10-6 Thermal expLnsion (Z/Ldl/dt) at 20’ C . 33 x 10-6 Hardness O Brinell 1 7.99 Tensile sirength (99.71% pure). tons per sq in. a According t o two different authorities.

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It is believed by several that changes will be made in the above values accredited to its specific gravity, its hardness, and its tensile strength.

USESFOR INDIUM Considerable work has been done on the electrolytic deposition of the element. Thiele (5) in 1904 deposited indium from a bath slightly acidified with sulfuric acid. Dennis and Geer ( 1 ) in 1904 used formic acid. Kollock and Smith (8) in 1910 used gelatin as an addition agent in the presence of free sulfuric acid, acetic acid, or sodium acetate. Mathers (3) used fractional electrolysis as a means for purifying the element. Recent work has shown that all of the above baths are very unstable. Daniel Gray found that sugars or carbohydrates added to a cyanide bath would stabilize it. Westbrook (6) reviewed the work of all except Gray and finally turned to a sulfuric acid bath containing sodium citrate. Fortunately Gray perfected a bath which is entirely stable. Kot only can indium be plated from this bath, but it can be plated simultaneously with other elements. Work has been concentrated not only on the plating of indium but also on its combinations with other metals. I n every case the addition of indium to other elements has especially increased the surface stability and also the hardness of the combination until indium is in excess. Patented processes have been developed which make the recovery of this element in substantial amounts entirely practical. By careful and systematic search of all known ores, a district was found which has very rich indium ore deposits. The indium seems to be a replacement in the ore of this particular district. By concentration, the ore has been made to yield a very high percentage of its indium content. These deposits will furnish substantial amounts of this element. Assistance can be furnished to those who wish to work with this metal, not only in the pure state but also in the form of many of its salts. Already several uses have been found for this element. It would seem to have use in the automotive, electrical, jewelry, and dental fields. There are undoubtedly many other places in which this element may be used. It would be desirable to know what it will do in medicine, radio, thermometry, and many other lines of work. Indium is no longer in the gram class, but is surely an ounce of metal. LITERATURE CITED (1) Dennis and Geer, J. Am. Chem. SOC.,26, 438 (1904). (2) Kollock and Smith, Zhid., 32. 1248 (1910). (3) Mathers, F. C., Ihid., 29, 485 (1907). (4) Reich and Richter, J . prakt. Chem., 89, 441; 90, 179; 92, 480 (1863). (5) Thiele, 2. anorg. Chem., 39, 119; 40. 280 (1904). (6) Westbrook, L. R., Trans. Am. Electrochem. SOC.,57, 289 (1930). RECEIVEDApril 18, 1832.

The Tung Oil Industry in the South HENRYA. GARDNER,2201 New York Ave., N. W., Washington, D. C , T ONE time the commercial production of rubbcr was entirely restricted t o trees growing in the wild state in the Amaaon Valley and other regions of the South American continent. Kot so many years a,go,an Englishman took a few rubber seedling trees from South America to the Royal Botanic Gardens at Kew, England, and with these a beginning was made in the orderly planting of rubber trees in grove formation in British possessions in the Far East. Had this step not been taken, it is probable that the antomobile never could have developed to its present high state of efficiency, and consequently the motor car industry would not have attaiiicd its present proportions. The situation in regard to tung oil in tlie American paint and varnish industry is somewhat analogous t o the early stages of the rubher plantation development. For thirty years all tung oil which has been used in our industry has come from thc Yangtae Valley and other regions of China. The industry has therefore been entirely dependent upon this single source for one of its most important raw materials. I n anattempt to make thiscountry more independent, seeds from tung oil trees were brought to the United States and grown into seedlings which were transplanted into groves. With these trees as a basis, a substantial beginning lias heen Inado toward the domestic production of tung oil wliicl~may eventually make usindependent of Chinaasasouree for this material. I n a relatively few years over 20,000 acres of trees have been planted in this country, and it is believed that within a few years there may be from 50,000 to 100,900 acres of these trees planted in the southern portion of the United States. Thus there has been begun a new industry for the South. COAIPOSITI~N AND SOURCE OP TUNR OIL C o m o s ~ n o ~Tung . oil is a product of the Aleurites species which is indigenous to China. The oil is composed p r i n c i p a l l y of the glyceride of eleostearic acid, containing, in addition, a g proximately 10 per cent of the glycerides of oleic acid, and from 2 to 3 per cent of the glycerides of saturated Catty acids. These acids are principally palmitic and stearic. The constitution of eleostearic acid is considercd by many students to be:

cent free acid. 'When produced by modem American machinery, a very pale, practically neutral oil is obtained. BOTANICAL DATA.The oil imported from China is derived from two varieties of the Aleuriteenamely, the fordii and the mrmtana. These trees are ornamental in character and rapid growers. In China they generally attain a height of 20 to 25 feet, with a trunk of about 10 inches in diameter, although larger trees have been observed. They have a lowbranching habit of growth and are inclined to produce a straggling head rather than a straight well-pronounced central trunk. They seem to require a minimum of fertiliaation, cultivation, and general care. The trees are deciduous, shedding their leaves in the autumn. The leaves are large and dark green in color and more or less heartshaped. The flowers, produced before the leaves, are white with pink centers and yellow stamens on the male blossoms. Each cluster of flowers is made up of one or more female blossoms, surrounded by male blossoms. The fordit variety grows in the Yangtae Valley region of China, while the m l a n a variety is found in the south. It has been determined that the fordii variety is best adapted to the conditions found in our Golf Coast States, while the rnataau variety succeeds in tropical regions. All the large planting8 in this country, therefore, consist of fordii trees. APPEARANCEOF FRUIT.The fruit is about the size and appearance of a small russet apple, being first a dark olive green and turning to a deep brown as maturity is reached. When fully ripe, the fruits fall and occasionally burst open from the base upwards, exposing five, or evcn seven, seeds which resemble the Brazil nut in shape and color, but, which are much smaller. The fruit ripens at approxim a t e l y t h e same time in both China and North America-that is, in Octoher.

COMMEIWIAL VALUE OF TUNG OIL Uses. The Chinese use tung oil primarily for waterproofing wood a n d o t h e r m a t e r i a l s . A f t e r heat treatment, it is also used by the Chinese as an ingredient in native lacquer. Soot obtained by burning t h e oil i s u s e d b y t h e Chinese in making ink. I n thiscountrytheprinciFINESPECIMEN OF TUNGOIL TnEE (Aicurites fordii) AT pal use for tung oil is in the CH,-(CH&CH: CHCN : CAIRO. Ga., PLANTED IN 1908 manufacture of varnishes CH.CH:CR(CH~),COOH and varnish paints. It is There are three double hands present, with a single bond also used in making insulating compounds; as an ingredient in between each double bond. It is to this closely conjugated automobile brakelinings; ingasliets for steam pipes; in linoleum structure of eleostearic acid that tlie well-known peculiar and table oilcloth; for waterproofing fabrics, paper, cartridge behavior of tung oil has been attributed. shells, etc.; as a hinder for wall board and plastic synthetic As found in its natural state in the cells of the seeds, tlie oil lumber; for lacquers, primers, pipe-coating plastics, synthetic is practically colorless and neutral in reaction, and, when re- resins, battery jar compounds, airplanetuhing fillers, etc. moved by cold pressing, it is light in color. Owing to the Ahout twenty-five years ago the use of tung oil with estericrude methods of handling the oil in China, the best imported fied rosin revolutionized the manufacture of varnishes in this tung oil is of darker color and may contain up to 7 per country. Previous t o that time high-grade varnishes were 687

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made with linseed oil and fossil resins. By the use of heat- chased two tracts uf land from B. F. Willirunson of Gainesville. treated tung oil, it became possible to make varnishes with On one of these tracts there was planted a nurscry of trees rosin esters, which were far superior to the old style fossil- grown from seed obtained from the University of Florida, and resin varnishes. A few years ago the introduction of nitro- on the two pieces of land the nurseries and groves of the celluloselacquers threatened to supersede varnishes, but certain Corporation have been developed. objectionable features of lacquers retarded their introduction The first extended plantings of tung oil trees in this country for general use. Moreover, the rapid development of synthetic were therefore made by the American Tung Oil Corporation. resins of many types enables the varnish manufacturer to pro- The object was to make a demonstration of the nossibitities duce quick-drying coatings of producing tung oil in the with a wide variety of uses. United States, and to transIn most of these new quickmit to agriculturists infordrying varnishes, tung oil is mation developed regarding animportant ingredient. I t proper methods of culture, would seem, therefore, that fertilization, etc. The trees the demand for this suhin this grove are now eight stance would continue to years old, and as early as the grow. third yesr began to produce IMPOR'PS AND VALUES fruit. In 1924 Benjamin Fignres compiled by the Moore and Company orUnited States Department ganised the Alachua Tung of Commerce for the period Oil Company and purchased 1922 to 1930 show that the a tract of about 2000acres imports of tung oil into this near Gainesmlle, Fia., which c o u n t r y increased from h a s been g r a d u a l l y de. 79,oM),000 pounds to over veloped into tung oil groves 12G,OOO,OOo pounds. The This work has been carried average value of these imout by IT. I. Ilaskins who ports was about $12,000,000 built the first tung oil pressper year. Although i t IS ing p l a n t in America. not yet possib1e to estimate T~~~N~ crrr~ R ~ 2b7l- ~ o N r wT~~~ BEAnrNo 232 FRrnTs Other interests made addithe average the tional plantings in north Grown without fertilmx om Omn&ebur soil at Citronella. 41a , LD 1929 plantlugs of tung ox1 trees in Clusts-variety tme.? prodwe L z e rluantit~esof irult central Florida, s o u t h e r n this country, it 1s probable Georgia, a n d t h e G u l f that between 50,000 and 100,000 acres, with about 100 trees Coast region of Alabama, Louisiana, and Mississippi It per acre, would be necessary to supply the quantlty of oil is estimated that there are now planted in this country a that has been imported from China However, some tung total of about 20,000 acres of trees, with probably 5000 adoil will probably always bc imported from China. ditional acres being planted this winter. An inspection of these groves is now being made by C. C. Concannon of the PLANTINGS OF TWNO OIL TREESIN THE UNITEDS,rnTEs Department of Commerce who has greatly aided in the work In so far as can be learned, David Fairchild, plant explorer which has been carried out. Tung oil trees have been grown successfully in Calrfornia, of the United States Department of Agriculture, was the first individual to bring tung oil seed into the United States. Alabama, hnisiana, Mississippi, and Florida. However, This was about the year 1905. This seed NF@ apparently California is not considered a favorable state for the complanted by Doctor Fairchild a t the Government Experiment mercial growing of the trees because of the lack of low-priced Station a t Chico, Calif., and the seedlings propagated there- land in sections where the soil and climatic conditions are snitfrom were distributed by him throughout Alabama, Florida, ahle. The largest plantings have been made in northern Louisiana, and Misskippi. During 1912 representatives of Florida, Mississippi, Louisiana, and Alabama. Large acrethe American Paint and Varnish Manufacturers' Association ages of low-priced land suitable for tung oil production are recommended to the Association that Fairchild's work be available in these four states. One of the largest tung oil groves in America is that of carefully followed up, and that larger plantings be made. During1921 the writermadeatripthroughthevsriousdistricts H. W. Bennett, 10 miles north of Gainesville, Fla. In where these trees were planted, observed the wonderful growth January, 1931, 2000 acres were planted in tung oil trees by attained by many of the trees, and again recommended that Mr. Bennett. The land is high and well drained, with a clay varnish manufacturers give carcfnl thought to the establish- subsoil a t a depth of 6 to 8 feet. Mr. Bennett produced hi8 ment of large producing groves. In the meantime, ten trees own trees in a nursery started a year previously and used only had been planted on the grounds of the University of Florida, selected stock. The pfanting was carefully done by a large and seed from these trees were planted by various individuals crew of workmen, operating 24 hours a day, the night work around the Gainesville district. To Wilmon Newell, Dean being done with the aid of flood lights. This grove is situated of the Agricultural College, University of Florida, is due the on a main highway and is entirely fenced in, with ornamental credit for the initial plantin@ in tho Gainesville district and plantine along the borders and other features which make to the carrying out of extensive experiments during the past it a show place. A large fresh-mater lake adjoins the grove, twelve years on cultivation and fertilization. Finally, in tempering the climate and supplying large quantities of 1923 tung oil advanced sharply in price and the attention of water hyacinth which have been used in mulching the trees. the American Paint and Varnish Manufacturers' Association Mr. Bennett has planted an additional 500 acres this year. At Picayune, Miss., Lamont Rowlands planted 4000 awe8 was again brought to the matter. During the annual convention of the Association that year, action was taken toward in tung oil trees in the winter of 193@-31. His land is at an the planting of a demonstration grove. The work was or- elevation of about 300 feet above sea level and is rolling in ganized as the American Tung Oil Corporation which pur- character. Mr. Rowlands followed a unique system of laying

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out and phntiug his groves, the rows of trees following the land contours rather than being perfectly straight. With tlie use of specially designed machinery, the land was plowed, and small trees and shrubs were cut down and broken up very quickly. By this method as high as 100 acres of trees were planted in one day, and tlie cost was said to be lower than that for any other grove. Mr. Rowlands is putting in an additional 2000 acres this year, and hopes that eventually there will he between 25,000 and 50,000 acres of groves in this section of the country, with an oil mill to take care of the seed produced in future years.

PLANTIKG REQUIREMENTS

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range in price from 55.00 to $15.00 per acre, and, with modern methods of clearing, the additional cost to put these lands in shape for planting should not be very great. A careful survey should be made of the soil to determine that it is suitable for the growth of the trees from the standpoint of soil constituents and drainage. It is most important to avoid soils of high lime content and with poor drainage. While the trees require copious rainfall, their roots should not stand in water. It is necessary, therefore, to he sure that the water table is a t a sufficient depth so that when the trees attain full growth with a fully matured root system, the ends of the roots will not be constantly immersed in water. Where proper drainage does not exist, the trees may do well for a few years and then hegin to deteriorate. I n preparing the soil for a tung oil grove, the usual operations are followed, including plowing and harrowing. The soil may be enriched by planting cover crops, such as cowpeas, velvet beans, beggarweed, or erotslaria, and plowing these under after they have matured. If seed is used to start a grove, i t should preferably be planted in a nursery. This permits of careful cultivation of the seedling trees and selection of the best for the grove. When the seedlings are one year old, they may be transplanted to the grove. Two methods of spacing the trees have been snggested-one with the trees about 15 feet apart in the rows and the rows about 25 or 30 feet apart, and the other with the trees and rows each 25 feet apart. If the trees are planted close together in the rows, the alternate ones could, if advisable, be removed after eight or ten years to prevent overcrowding. However, the prevalent idea is that the greatest yields will he obtained by planting 200 trees to the acre and leaving the trees permanently in place. To obtain high yields of fruit, a fairly liberal application of fertilizer should b e given t,he trees, a t leest during the first eight years. The use of cover crops in the “middles” will help e n r i c h t h e soil and prevent the growth of weeds. T h e soil around the trees should be cultivated and kept clean. The p a s t u r i n g of sheep a n d c a t t l e in t h e groves will save much laborin cutting weeds and grass and provide some additional fertiliaer.

As a resnlt of the early work in the growing of tung oil trees in this country, a rather definite zone was established in which tung oil trees could be grown suceessfully. In general, this none extends from near the southern border of Georgia to the south central part of Florida, and westxard along the Gulf coast of Florida, Alabama, Louisiana, and Mississippi. The blossoms are very sensitive to early spring frosts and have not infrequently t x m killed in certain regions north of Florida. The tree itself, when established, is hardy enough to resist occasional frost hut will not thrive in areas subject to extended periods of frost. I n addition to the climatic range for the successful growth of tung oil trees, certain other definiterequireinentsliavebeen developed by the work to date, and will be summarized below. Further studies are being made by various investigators, particularly Harold Mowry, assistant liortieulturist of the Agricultural College, University of Florida, and other members of the staff. These studies include budding, grafting, fertilization. soil types, seed selection, ete Fortunately, no serious diseases or insect pests have been discovered on tung oil trees grown in this country. The trees have in some instances been retarded in growth and even killedhy improper soil conditions. These c o n d i t i o n s a r e not t h o r o u g b 1y understood a t the present t i m e , h u t evidence gathered to date indicates that the effect known as chlorosis (a fading of the leaves) is caused by excessive limestone content in I’XESSING THE OIL t h e soil, while the effectknown asbronzThe harvesting of ing seems to be asthe fruit is ~impleessociated with an expecially if the ground cess of t r i c a l c i u m IZOLLING T U N 0 011. FnlIlT IN BAUER HULLERFOR EXPRESSION IN is f r e e o f u n d e r ANncnsow EXPELLEER nhnsohate at certain erowth. The fruit depths in the soil. ;pens in October and For the economical production of tunr: oil. land should be November and falls to the ground where it may be allowed to selected which preferably will not cost over &l0.00 per acre remain until a convenient gathering time, as the husks While lands which have been previously farmed may he used, protect the seed for a long time When fairly dry, the fruit it seems to he established that much better results are ob- may be raked up and loaded in oarts or trucks and hauled to a tained on new lands which must be cleared. Old lands which barn or shed where a further drying period may be allowed. have previously been cultivated are usually worked out and Satisfactory machinery is available for removing the husks the soil is in poor condition, whereas newly cleared land seems and inner pellicles and pressing the seed. Central tung oil to give exceptional groves which cannot he approached by mills, similar to the sugar eentrales in Cuba, should be the old worked-out lands. There are millions of acres which established in the various districts in which the groves are

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concentrated. One mill has been erected at Gainesville, Fla., which is probably capable of handling all the fruit that will be produced in that area for some years to come. The plant represents an investment of about $15,000.00 and has a capacity of 50 gallons of oil per hour. The rate of intake is approximately 3000 pounds of fruit per hour, which is sufficient to supply an additional oil-pressing unit of the same capacity as that in operation at this plant. The entire operation is automatic from the delivery of the whole fruit to the decorticating machine to the production of the oil. The husks are of little value, although they may possibly be used for adding humus to the soil. The press cake contains very little oil and has some value as a fertilizer. YIELDSOF OIL. Some individual trees, after seven years of growth, have given yields of up to 2 gallons or more, which would indicate 200 gallons per acre. This, however, is unusual and could not be expected as an average figure for a whole grove. It is probable that a yield of 50 gallons per acre from groves ten years of age would be sufficient to justify the planting of such groves in a large way. However, under fortunate climatic conditions and with good soil and drainage

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it is probable that considerably larger yields will be shown, but none of these figures will apply unless proper soil and drainage are supplied. ACKNOWLEDGMENT The writer wishes to express his appreciation for the cooperation given by C. C. Concannon, chief of the Chemical Division, Bureau of Foreign and Domestic Commerce, United States Department of Commerce, in furnishing during the last eight years monthly cable reports on the exports of tung oil from China, and in other ways. Julean Arnold, United States Commercial Attach6 at Shanghai, China, has also been of service. The Department of Commerce now has in preparation a publication on tung oil which should be of great value in stimulating the development df this new industry which promises to be an important activity for the Gulf Coast region of the United States. RECEIVED March 8, 1932. Presented before the Division of Paint and Varnish Chemistry a t the 83rd Meeting of the American Chemical Society, New Orleane, La., March 28 t o April 1, 1932.

The. Tennessee Copper Basin EMERSON P. POSTE,P. 0. Box 51, North Chattanooga Station, Chattanooga, Tenn.

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EFERENCE to a map of the territory formerly occupied by the Cherokee Indian reveals the fact that many present geographical names are of Indian origin, often honoring some prominent chief of the early days. One of these worthies by the name of Duck is commemorated in the name “Ducktown” which refers not only to a village but to the surrounding district which has long since become well known as a copper-producing area. I n more recent years the manufacture of sulfuric acid and other by-products has been developed to such an extent as to make this territory a center of chemical as well as metallurgical interest. GEOLOGICAL FEATURES The Copper Basin is located in the extreme southeastern corner of Tennessee, bounded east and west by two ranges of mountains approximately five miles apart. To the north is a lateral ridge, five miles south of which the Ocoee River cuts across the district. I n the Basin the formation is metamorphosed sedimentary material of Lower Cambrian origin, with some small igneous bodies. The ore deposits are enclosed in the sedimentary rocks as calcareous replacements, the source of the mineralizing solutions being unknown. They lie at an average angle of about 30” from the vertical. The lodes contain three distinct zones of ore. The outcrops are typical gossans with hydrated iron compounds predominating to depths of 100 feet. Below this zone is a layer of secondary enrichment high in chalcocite, locally termed “black copper,” containing from 20 to 40 per cent copper. Some free metahc copper is also found in this portion. Below this is a body of “yellow” sulfide primary ore extending beyond depths of exploration. The copper content of this material ranges from 1 to 2.5 per cent.

HISTORY OF DEVELOPMENT Based on Indian relics discovered near the Ocoee River in

1880,it is reported that the red men may have carried on some

early metallurgical operations, for with their pottery and other items, pieces of copper ore and slag and a slab of metallic copper were found. But the presence of copper ores does not seem to have been known to the white settlers until the late forties. There was quite general prospecting for gold throughout this territory in the early days, and, while panning a t what is known as the Burra Burra lode, one of the searchers found copper minerals which attracted attention. No systematic exploration was made, however, until 1847 when about 15 tons of ore were shipped to a refinery in Boston, yielding about 25 per cent copper. The same year an effort was made to use ore from another gossan in the manufacture of iron, but the quality of the product did not prove encouraging. Definite mining did not begin until 1850. The ore was hauled out by wagon to Dalton, Ga., a distance of 60 miles, and shipped to northern smelters. I n 1853 a road was constructed along the Ocoee River bed to Cleveland, Tenn. (a distance of 40 miles), affording favorable railroad connections, and by the latter part of 1855 the industry had taken on considerable proportions. During these early years several companies had been working, and many small mines and five local smelters had been constructed. The rich black ores produced a matte which found a ready market at the northern refmeries. I n 1858 a combination of the small companies took place, and a refinery was built in Cleveland. This was, in time, followed by a rolling mill and wire works, and a good volume of copper products resulted. Records vary as to the Civil War period. Some indicate that operations were suspended until 1866; others state that the district “supplied nearly all the copper used in the Southern States from 1861 to 1865.” It is evident that important reorganizations and rapid developments took place during the period 1866-77. New smelters were constructed; narrowgage tracks took the place of less adequate means of haulage; equipment in general was greatly improved. But the rich black ores were becoming exhausted. The poorer ores could