RME- 4062

U. S. ATOMIC ENERGY COMMISSION

DIVISION OF PRODUCTION AND MATERIALS MANAGEMENT

POSSIBILITIES FOR URA\NIU14 IN

By

Edward K. Judd

Washington, D. C. 20545

January 1955

metadc1 393263 REPRODUCED FROM BEST AVAILABLE COPY

Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

-2- RME- 4062

POSSIBILITIES FOR URANIUM IN COSTA RICA

CONTENTS

Page

INTRODUCTION ...... 4 Geography ...... 4 Transportation, communication and industry ...... 4 Physiography and climate ...... 6

GENERAL GEOLOGY ...... '. . . . . 7 Deep-seated intrusives ...... 8 Extrusive and eruptive rocks ...... 9

METALLIC LODE DEPOSITS ...... 10

SUMMARY .. . * ...... 0 . . . . .0 0 .0 0 . 13

REFERENCES ...... 0...... 14

ILLUSTRAT IONS

Figure 1. Political map of Costa Rica . . . . . 0 . . . * . . . . 5

Plate I. Geologic map of the highlands of Costa Rica . . . . (in pocket)

- 3 - RME-4062

POSSIBILITIES FOR URANIUM IN COSTA RICA

INTRODUCT ION

Geography

The Republic of Costa Rica occupies the full width of the Central American isthmus, a minimum of 120 kilometers (75 miles) at this lati- tude, between Nicaragua on the north and on the south (Fig. 1 . The approximate limits are N. 80 (Point Burica) to 110 15' and W. 82 30' to 86 . Its area is about 50,890 square kilometers. is in the Pacific, about 300 miles to the southwest.

At the end of 1951 the estimated population of 838,084 was distrib- uted among seven provinces -- San Jose, 293,891, , 155,384; , 105,259; Guanacaste, 94,186; , 92,205; , 53,725; and Limon, 43,434. During 1949-1951 immigration and emigration almost balanced. In descending order of population the chief cities are San JosE (the capital), Alajuela, Puntarenas, Cartago, Ileredia, Lim6n and (of Guanacaste). Most of the people are European (mainly Spanish) descendants; about 15,000 West Indians are largely in Lim6n; native 'Indians are few.

The chief seaports are Lim6n on the Caribbean and Puntarenas on the Pacific side. The United Fruit Co. also maintains ports at and on the Pacific.

Transportation, communication and industry

An intercoastal railway from Lim~n to Puntarenas passes through Cartago, San JosE, Heredia and Alajuela. Another railway to connect Limnon with Almirante (Panama) lacks only a middle section now under construction. The Costa Rican segment of the Inter-American highway, passing through San JosE, has 204 kilometers completed with 300 to follow. Motor roads generally are in good condition and total about 350 miles. There is no road into Panama and only one (passable just in dry weather) into Nicaragua. Passenger traffic into and out of the country is mostly by air. The international Pan American, Taca and Royal Dutch lines use a landing field at La Sabana near San Jos6, and their subsidiaries give daily service to important other towns.

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- 5.- Commercial wireless telegraph stations are located at Cartago (international service), Limon (service to Almirante), Puntarenas, Quepos and Golfito. The government also has 19 wireless stations serving San Jose to Nicaragua, Honduras, San Salvador and Mexico. It further has 202 official telegraph stations and 88 for telephones. (3).

Agriculture is the main industry, with some dairy farming and cattle raising. About 1,877,000 acres is under cultivation, 543,000 acres in pasture, while 9,855,000 acres of forest, much of it in the public domain, contains several varieties of valuable timber, cut mostly on the western side. The chief products are coffee, bananas, cocoa, sugarcane and tobacco. A few factories in the larger cities are engaged mainly in the processing of primary produce. Nationalized hydroelectric power is extensively developed. Although gold mining has been practiced in the Guanacaste and Aguacate mountains, known deposits of other ores are but slightly explored.

Physiography and climate

The main mountain ranges of Mexico and'Central America continue southward and traverse the whole length of Costa Rica from the northwest to southeast with only one important interruption, the valley occupied by the Rio Grande flowing to the Pacific and the Rio Reventazon the the Caribbean. Both rivers have their headwaters near Cartago, and their valleys afford a convenient route for the intercoastal railway. The two principal ranges north of this narrow depression, "lMeseta Central," are the Cordillera del Guanacaste (with high points at volcanoes Mira- valles and Canaste) and Cordillera Central (with several active vol- canoes -- IrazEi, , Barba and Pogd. South of lMeseta Central are the short Bustamante Mountains and the mugh longer Cordillera de . The latter reaches almost to the Panama boundary and rises to the highest elevation in the country, 3837 meters, at Chirrip6 Grande.

The Meseta Central is covered by fertile volcanic ash and supports about three-quarters of the country's population; four of the largest cities are situated here. The region, however, has often been afflicted by disastrous earthquakes.

The marshy Caribbean coast is about 130 miles long. It is fairly straight, characteristic of a rising shore, and bordered by lagoons. The Pacific coast, about 630 miles, is much more irregular with many small and two large indentations -- the Gulf of on the north, a shallow bay between Nicoya peninsula and the mainland; and the Golfo Dulce on the south, having peninsula at its west side. This shore topog- raphy indicates a sinking coast. Contras-ting with the mountainous interior of Costa Rica are large areas of lowland (below 100-meter elevation) and narrow strips along both coasts. The largest of these lies north of the mountains. It extends northward into Nicaragua and occupies the whole width of the Central American isthmus. The boundary Rio San Juan, draining Lake Nicaragua, flows easterly through this Nicaraguan depression" and was to have facilitated construction of the projected Nicaraguan canal. There is another large expanse of lowland to the north and west of the. head of Nicoya Gulf, a major part of . A third area borders Golfo Dulce and Osa peninsula near the Panama boundary.

Costa Rica has many short but steep rivers, extensively utilized for power, as well as several longer ones with gentler gradients. The largest tributaries to the Rio San Juan from the Costa Rican side are the rios Sabogal and , in , and the Rio Chiripi, bounding Heredia and Limon provinces. The Rio Tempisque drains the lowlands north of Nicoya Gulf. The interinontane San Jose basin originates the rios Grande and Reventazon. Headwaters of both rivers probably are fairly swift, but both cross lowlands at their mouths. Similarly the Rio Diquis in has steep headwater tributaries and traverses a considerable width of lowland.

The climate of Costa Rica is diversified according to altitude. In the humid jungles along the Caribbean coast the average annual rain- fall of 120 inches is distributed over all seasons. The narrower Pacific lowland is somewhat drier. The highlands west of the mountains have two seasons, the dry season occurring from December to April. San Jose city is renowned for its equable springlike climate (4). Most of the mines of Guanacaste Province are in this highland belt at elevations of 200 to 500 meters.

GENERAL GEOLOGY

A striking feature of Costa Rica's geology is the contrast in com- ponents and structure between the mountain ranges north and south of the rios Grande-Reventazon valleys, traversed by the intercoastal railway. So far as now known, those to the north -- cordilleras Guanacaste and Central -- consist entirely of extrusive and volcanic igneous rocks. The southern ranges -- Candelaria, Bustamante and Talamanca -- have a more complex structure involving sedimentaries, metamorphics, and intru- sives of two or more epochs (P1. I).

According to Sapper (5), neither Precambrian nor Paleozoic strata had been identified in Costa Rica up to 1937. Schists and altered limestones do occur, but their originals were strata of much later date. The earliest definitely identifiable measures are late Eocene limestones that are exposed in a small area in the Rio Reventazon valley just east of the Turrialba Railway station. While certain breccias, conglomerates, sandstones, shales and limestones along the northwestern coast possibly may be older Eocene, their ages have not been thus proved. They are

- 7- unconformably overlain by other shales and silicified limestone (age uncertain), and all are largely buried under Tertiary volcanics. On Nicoya peninsula Romanes (6) found no trace of old metamorphic rocks such as had been mentioned by previous visitors. Pittier's suggestion that such rocks occur on some high ridges of south-central Costa Rica has not yet been confirmed.

The Oligocene is extensively developed on both sides of the central range of southern Costa Rica. It occupies large areas in the Candelaria highlands and on Cerro Bustamante; along the southwestern foothills of the Cordillera de Talamanca between longitudes 840 and 830; among the headwaters of the Rio Estrella on the Caribbean slope; and in patches at about the middle of Nicoya peninsula. The formations reach a thickness of 300 to 400 meters within a small exposed area on the north side of Cerro de la tMuerte (or de la Vuelta) in the northern Cordillera de Tala- manca. Oligocene rocks include a basal conglomerate with andesitic pebbles, followed by variegated marls and interstratified quartzites, sandstones, breccias and limestones. In the Rio Estrella area the for- mation consists of 600 meters of green shales resting upon calciferous sandstone and passing upward into other sandstone (5).

At some of the above named localities the formations called Oligocene probably include some strata of early lMiocene age. Definitely middle and late IMiocene beds (Gatun formation) crop out *in the foothills on the Caribbean side at Lim6n, and between the Rio Estrella and the Panama boundary on the Rio Sixaola, as well as on the Pacific coast just south of the mouth of the Rio Grande. Limestones of undifferentiated Tertiary ages form a belt along the Pacific foothills in the Cordillera Brunquena of southernmost Puntarenas Province.

D ep-ete nt rusives

Although deep-seated granitic rocks are yet unknown in northern Costa Rica (a granite boulder found in suggests their presence), they are prominent inmponents in the Talamancas of the southern country. The date of their intrusion has been in dispute, and is a matter of much importance bearing on a search for uranium in their vicinity. Gabb (7) an early investigator, considered their age to be late Tertiary, chiefly because an immediately overlying and early Tertiary' conglomerate con- tained no pebbles of the granitic rocks; however, he found no pegmatitic offshoots from the intrusive mass. Hill (8) likewise assigned a Tertiary age to the granites of Costa Rica and Panama, or slightly older in some cases. Lohmann (9), Larde (10) and Sapper (5) agree that the central core of the Talamancas is the remnant of an old granitic range (possibly latest Paleozoic as proved farther north in Central America). Willis (11) maps these granitic rocks as "post-Cambrian intrusive," entirely distinct from the more widely extended Tertiary extrusives.

- 8- The practical aspect of this age question is that, if the granites are older than the most ancient formations now in visible contact with them, the latter cannot contain any ore deposits traceable to these in- trusives, and acidic magmas have been the almost invariable source of uraniferous lodes. In the Talamancas, however, the intrusive mass itself consists mainly of granite and syenite and may possibly contain mineralized fissures or fractured zones representing the final stage of its solidification. The mass of monzonite in the central Candelaria highlands) vicinity of , may be affected in the same way, also the syenite on Cerros de Escastd. Examination of granite boulders at (13 kilometers due west of San Jose) disclosed interstitially crystallized pyrite, apparently a late mineralization (20).

Exrsv n eutv ok

Rocks of this type blanket nearly the whole of northern Costa Rica and considerable parts of the south. They occur most often as lava flows but also form sills and dikes. In the latter case they do not lose their characteristics as shallow extrusives distinguishable from deep-seated intrusives. Beds of tuff found occasionally among the earliest limestones show that volcanism began at least in early Tertiary time, and apparently continued, almost to the present day.

Andesite predominates, with variations generally toward more basic varieties. Putnam (12) offers evidence to indicate that these extrusives were all derived from a common magma. About the most acidic variety is rhyolite, or quartz porphyry, which occurs between Liberia (N. 10-36, W. 85-25) and (25 kilometers southeast) in Guanacaste. Monzonite (possibly intrusive) in the central Cordillera Candelaria south of the San Jose basin is a moderately acidic rock, associated with uraniferous ore deposits at one place in the western United States. The omnipresent andesite is the host rock for the gold-quartz veins on the southwestern slopes of the Cordillera del Guanacaste.

Among the basic and ultrabasic varieties (negligible as possible sources of uranium deposits) are: (1) limburgite at Manzanilla; (2) diabase and dolerite on Nicoya peninsula; (3) gabbro on Cerro Escasl; (4) relaphyre on the Rio Candelaria; and (5) diorite at and Sardinal, and at various places in .

Porphyries (of unidentified types) are widely scattered, usually as dikes, in Guanacaste, San Jose and Cartago provinces. One especially prominent forms the apex of Pico Blanco in extreme south Limon Province. In the upper Rio Reventaz6n valley Gabb (7) noted the proximity of por- phyry dikes to the auriferous copper veins of that area, though the veins were always a mile or more remote from exposed granite.

- 9- METALLIC LODE DEPOSITS

Mineralized lodesor sheeted zones have long been our chief sources of uranium ores. In the future their supremacy may be contested by secondary ores of the carnotite type and by those of sedimentary origin, but neither of these latter seems likely to be found in Costa Rica. The country, however, does contain many lode deposits similar to some of those in the western United States from which uranium ores have been produced.

Lode mining in Costa Rica has been concerned almost exclusively with gold. During recent years this once flourishing and moderately remunerative industry has undergone a serious decline, mainly through exhaustion of ore reserves of a grade able to cover the increasing costs of production, which have always been high (13). As a guide to uranium gold itself is less suggestive than the accessory minerals and gangue of the ore. Further, it is less indicative than the apparent source of the lode filling and the manner of its deposition. One should particularly note that an occurrence of uranium minerals does not depend on the mag- nitude or productivity of an ore deposit. Most of our present supply of uranium ore from lodes is in mines that could not operate profitably for any other reason.

The gold mines of the country occupy two fairly close areas, both on the west flanks of the Cordillera del Guanacaste, facing the Gulf of Nicoya. The northern group includes most of the older mines. It extends in a belt, at a 200- to 5OO-imeter elevation, southeasterly from around Las Juntas of the district to Miramar 17 kilometers northeast of Puntarenas. The southern group lies south of San Ramon on Aguacate mountain, just north of the San Jose valley at , of southern Alajuela Province.

In both areas the country rocks are Tertiary andesitic flows, which differ somewhat in composition and texture, tending toward dolerite. They are believed to have originated in a common magma underlying large parts of Central America (12). The quartz veins and silicified shear zones represent a late phase of the same volcanism, and offer evidence of a medium- to low-temperature hydrothermal deposition. In some cases the wall rocks are much decomposed hydrothermally as well as by ordinary weathering (14).

Malozemoff (15) names the following mines in the northern area (without description or precise location):

(1) Abangarez mine (presumably near Las Juntas, N. 10-15, W. 84-57), most active 1903-1928; worked by lessees 1932-1942 or later; idle in 1949 (13).

. (2) Santa Elena mine "on the lower Barranca River" (probably up- stream from San Miguel, N. 9-59, W. 84-40); idle in 1942.

- 10 - (3) Bonzanza mine, "near the old La Union mine" (N. 10-12-30, W. 84-47; 5 kilometers northwest of Miramar); operating in 1942 and the only mine active in early 1949 (13).

(4) Montezuma mine (location uncertain); some small activity in the vicinity in 1942.

(5) Guacimal (N. 10-13, W. 84-51; 15 kilometers southeast of Las Juntas); a lead-silver vein in the vicinity has been worked intermittently.

Several mines operated prior to 1896 in the San Ramon or Aguacate district, about midway between Puntarenas and San Jose, and just north of the railway connecting these cities. Church (16) described the deposits as auriferous veins of quartz mixed with decomposed feldspathic rocks. The Guapinol and Los Castros mines were the earliest, with veins 6 to 7 feet wide. The vein at the Quebrada Honda mine is 16 feet wide. The ore was refractory (to amalgamation) with sulfides and considerable copper.

More recent mining activity on Monte Aguacate about. 1942-1946 had ceased by early 1949. As active in 1942 Malozemoff (15) names the Compania mine with a flotation plant, and Mina Union de Aguacate using amalgamation and table concentration.

Rex (17) described conditions in 1946 on Monte Aguacate and the mineralogy of Los Castros vein. The area can be reached by two routes: (a) from San Ramon on the Pan American highway, by dirt road (for jeep, oxcart or horse) south to de San IMateo; or (b) from the Con- cepci~n railway station, about halfway from Puntarenas to San Jose, by trail up a steep mountain on the north, then along a ridge nearly level almost to Desmonte; 1 hour by horse, 2 hours on foot.

Among about fifteen mine tunnels on Monte Aguacate three were working in 1946 -- San Juan, Don Fabio and . All belonged to the Cia. Aurifera Nacional de Costa Rica, which was operating San Juan. The other two were being worked by the Rosario Mining Co., which then held an option on all three. The mountain consists mainly of -extrusive andesite from either Pots or ]3arba volcano. A loose cover of bombs and ashes has mostly been eroded, leaving only a thin mantle over the solid rock. While the axis of the mountain is about east-west, the veins -strike north-south and have been opened chiefly on their south ends. A few tunnels on the north side were abandoned long ago.

The several nearly parallel veins are obviously fault fractures generally filled by crystalline quartz and chalcedonic silica; rhodonite is a frequent accessory gangue mineral. Ore minerals are found in the greatest variety in the old (now difficultlyaccessible) Los Castros tunnel. They include: massive chalcopyrite in narrow veins with rhodo- nite and yellow to deep brown sphalerite; galena, often argentiferous, in crystals and pockets within quartz; native gold-silver in fine dis-

- 11 - deminated grains or small plates in or on quartz; pyrite in very small cubic crystals attached to auriferous quartz; stibnite in radiating groups of slender prisms up to 1 1/2 inches long within quartz. This assemblage strongly suggests a hydrothermal origin favorable for an occurrence of pitchblende.

Showings of copper sulfide minerals, in float and in narrow, unwork- able stringers, are reported from an area at the extreme northwest end of the Cordillera de Talamanca, just south of the San Jose basin (15). The named localities are:

(1) Concavas (N. 9-50, we 83-52), 4 kilometers east-southeast of Cartago and on the north bank of the upper Rio Reventazo'n; some underground development wss done here.

(2) San Ignacio de (N. 9-47-30, W. 84-08), 20 kilometers southwest of San Jos4.

(3) Puriscal (N. 9-51, We 84-19), 30 kilometers west-southwest of San Jose.

Similar showings occur also on the southern slopes of Irazu~ volcano north of Cartago in the upper Rio Reventaz6n valley.

Lohmann and Schaufelberger (18) mention a copper-bearing quartz vein in marl and soft sandstone at Atirro (N. 9-51, we 83-40), on the south side of the Rio Reventaz~n and 7 kilometers south-southeast of the Turni- alba Railway station.

In the same general region Fraser (19) adds, as sites of workings in gold-silver-copper ores, Paraiso (N. 9-50, we 83-51; on the railway 6 kilometers east of Cartago), Orosi and El Copey, respectively 6 and 22 kilometers south of Paraiso. Schaufelberger (20) mentions auriferous quartz veins (unworkable) in the Pejibaye and Tuis valleys, south tribu- taries to the Rio Reventaz6n at about W. 83-40.

Since copper sulfides are one of the mast consistent companions of pitchblende, the mentioned stringers deserve a radiometric survey in spite of their apparent insignificance as producers of copper.

Bearing additional evidence to the prevailing low-temperature min- eralization of the Tertiary ore deposits, Schaufelberger (21) notes that cinnabar was once and briefly mined in the Rio Grande valley. There is a record of torbernite associated with cinnabar at a Mexican locality.

D6ndoli (22) describes a galena-blende-pyrite mineralization in fractures and sheeted zones in black limestone along the Rio Salitral in southern Santa Ana rnunicipio (N. 9-56, W. 84-11; 13 kilometers west of San Jose). The Pb-Zn sulfides are disseminated in a mass consisting largely of oxidized pyrite; the galena carries only a trace of silver.

- 12 - The deposits are obviously hydrothermal and probably due to an intrusion of diorite, which is slightly exposed farther upstream. No extrusive andesite or basalt occurs in the vicinity. The author discounts the workability of these deposits, and they offer little or no hope for uranium. However, they are significant evidence of mineralization from a deep-seated source, a rare phenomenon (as yet known) in Costa Rica.

SUMMARY

Costa Rica is not known from published reports (none of recent date) to possess any definite indications of uranium. Conditions affecting the presence of uranium are discouraging though not hopeless. Chiefly adverse are: (1) the complete absence of Precambrian or even Paleozoic meta- morphic rocks, the favored sites of uraniferous lode deposits; (2) the scarcity of highly siliceous intrusive bodies like those to which many uranium lodes are traceable; and (3) the massive intrusions of moderately acidic granites and syenites in the Talamanca ranges, which might possibly have generated uranium minerals, are all probably older than the most ancient formations now seen adjacent to them; therefore, the latter cannot have been mineralized by those intrusives.

Faintly encouraging circumstances are:

(a) The same massive intrusives, forming the core of the Talamancas, may within themselves have developed uraniferous mineralized lodes or fractured zones as a final phase of their solidifica- tion. Some of the porphyry dikes intruding the granitic masses also may have caused favorable mineralization.

(b) The gold-quartz veins of the southern Cordillera del Guanacaste apparently owe their source to some more acidic phases of the Tertiary andesites in which they occur. At several places in the western United States uranium has been found in variously mineralized lodes traceable to Tertiary intrusions.

(c) The narrow quartz veins reported to occur along the south wall of the San Jos&-Cartago basin carry some of the metallic min- erals, in addition to gold, that have commonly been noted as present in uraniferous lodes.

- 13 - REFERENCES

1. ------, 1953, Atlas estadrstico de Costa Rica: Ministerio de Econonia y Hacienda, Direcci~n General de Estadrstica y Censos, 114 p.

2. ------, 1945, Mining and manufacturing industries in Costa Rica: U. S. Tariff Comm., 16 p.

3. ------, 1953, Statesman's yearbook for 1953: New York, St. Martin's Press, p. 881.

4. ------, 1952, Columbia Lippincott gazetteer of the world: New York, Columbia Univ. Press ,p. 455.

5. Sapper, K., 1937, Handbuch der regionalen Geologie, Mittelamerica, v. 8, Abt. 4a, 160 p.

6. Romanes, J., 1912, Geological notes on the peninsula of Nicoya, Costa Rica: Geol. Mag., ser. 5, v. 9, p. 258-265.

7. Gabb, W. M., 1874-1875, Notes on the geology of Costa Rica: Am. Jour. Science, ser. 3, v. 7, p. 438; v. 9, p. 198-204.

8. Hill, R. T., 1898, Geology of Costa Rica and Panama: Harvard Coll. Mus. Comp. Zoology Bull., v. 28, no. 5, p. 151.

9. Lohmann, W., 1934, Stratigraphie und Tektonik des Hochiandes von Costa Rica: Geol. Rundschau, v. 25, p. 10-26 (April 4).

10. Larde, J., 1924, Geologia general de Centro America, y especial de El Salvador: San Salvador, Imprenta Nac., 82 p.

11. Willis, B., 1912, Index to the stratigraphy of North America: U. S. Geol. Survey Prof. Paper 71, 894 p.

12. Putnam, P. C., 1926, Existence of a once homogeneous magma mass underlying Central America: Jour. Geology, v. 34, p. 807-823.

13. May, S. and others, 1952, Costa Rica, a study in economic development: New York, Twentieth Century Fund, p. 114-115.

14. Romanes, J., 1912, Geology of a part of Costa Rica: Geol. Soc. London quart. Jour., v. 68, p. 103-139.

15. Malozemoff, P., 1942, Costa Rica: Eng. and Min. Jour., v. 143, no. 8, p. 113-114.

16. Church, C. E., 1897, Costa Rica: Geog. Jour., v. 10, no. 1, p. 56-84.

- 14 - 17. Rex, Robert, 1946, The gold mines of Monte Aguacate, Costa Rica: Rocks and Minerals, v. 21, no. 9, p. 561-563.

18. Lohmann, W. and Schaufelberger, P., Uber die Talamanca.-Kordillere und das Reventazon-Tal von Costa Rica: Centralblatt f~ir Mineralogie, Geologie und Palaontologie, Jb. 1934, Abt. B, p. 204-208.

19. Fraser, L., 1911, Mineral resources of Costa Rica: Mim. and Sci. Press, v. 102, p. 130.

20. Schaufelberger, P., 1931, Apuntes de geologia: Costa Rica: San JosE, 83 p.

21. Schaufelberger, P., 1932, Un estudio elemental sobre la geologia de Costa Rica: La Escuela Costarricense, v. 1, no. 3, 56 p..

22. Dondoli, C., 1941, Los minerales de Costa Rica: Dept. Nac. Agric., Bol. Tech. 34 (Ser. Geol. no. 5), 7 p.

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