Provincial Geographies of India/Volume 4/Chapter 8
CHAPTER VIII
MINERALS
The very name of Burma is associated in our minds with rubies and other precious stones, and yet the combined value of the rubies, sapphires and spinels extracted from the mines in 1919 was not half that of the tin, not a quarter that of the tungsten or of the silver, less than a sixth of the value of the lead output, and less than one-sixteenth that of petroleum. Burma, although not a store-house to the fabulous extent ordinarily believed of precious stones, is undoubtedly the richest province in minerals of the Indian empire. It is now proposed to give an account of these minerals seriatim.
Burmese Amber varies in colour from a pale yellow to a dull brown, and resembles a variety found in Sicily in the possession of a peculiar fluorescence. It is heavier, harder and tougher than that obtained on the Baltic coast. It is conjectured that the resin from which it was formed exuded from trees which flourished during the "gulfs" period described in the preceding chapter (Miocene). It is found in the Hukong valley in the extreme north of Burma, where it is dug out of a blue clay at depths of from 20 to 40 feet below the surface. Mandalay absorbs most of the material, which is sold in the form of rosaries, ear-cylinders and other ornaments. When rubbed with a non-conducting cloth amber acquires a charge of electricity, our word for the latter being derived from elektron, the Greek word for amber. Its use for pipe, cigar and cigarette mouthpieces is due to a belief of the Turks, whose custom it is to pass the pipe from one to another, that no infection can be transmitted.
Antimony in the form of the sulphide, stibnite, is known in the hills behind Moulmein, and also in the Southern Shan States, but none of these deposits is rich. Stibnite is used by oriental beauties for blackening the eye-brows.
Barytes, Heavy-spar or Sulphate of Barium, as it is variously called, has been discovered in considerable quantity at Bawdwin in the Northern Shan States, and is used as a flux in the smelting of the silver-lead ores. Barytes can also be used as a white pigment and as a body for certain kinds of paper and cloth.
Bismuth in small quantities is associated with the antimony found in the hills opposite Moulmein, and occurs in considerable amount at one spot in the mines of Bawdwin. Compounds of the metal are employed for medicinal purposes, and the metal itself is a constituent of certain alloys with an unusually low fusibility.
Burma is well off in Building stones. Limestone in almost unlimited quantity but of a somewhat brittle tendency occurs in the vicinity of Moulmein; another band of good quality is known in the Bassein district. A chocolatecoloured limestone has been quarried near Zibingyi between Mandalay and Maymyo. A beautiful white marble comes from the Sagyin Hills north of Mandalay, and is much used in the manufacture of carved images of Buddha and for ornamental purposes by the Burmans; a similar marble occurs in large quantities at Kyauksè, south of Mandalay, and in the Ruby Mines sub-division. The "Plateau" limestone of the Shan plateau is, most of it, only fit for roadmetal. Laterite is a rusty-red rock and derives its name from its quality of being easify cut up into rectangular blocks (Latin, later, "a brick"); the great bulk of the Burma supply comes from the Irrawaddy valley. Yellow, purple and pink sandstones are quarried near Toungoo. The granitoid gneiss from the Thatôn quarries has been largely used on the Burma railways and for land reclamation in Rangoon. Lime is manufactured from limestone at Tônbo, not far from Mandalay, at Zibingyi and at Thayetmyo.
One mineral of which Burma has felt the lack most acutely is good Coal. Coal of a kind is plentiful and ubiquitous enough, but it is always a Tertiary lignite, with low fixed carbon and high ash and water percentages. The best known seams occur in the Northern Shan States, in
Fig. 30. Gold washing in the Chindwin River.
the foothills of the Arakan Yoma in the Minbu and Henzada districts, and on the Kale river in the Upper Chindwin district. In the Shan States the Lashio and Namma fields are the most important, the latter possessing very large reserves of a lignite of less inferior quality.
Rich Copper ore has been discovered in the silver-lead Mines at Bawdwin. Little is known as to the quantity available but this is probably large.
Gold is found in a large number of the Burma rivers and streams, but its extraction has not proved a lucrative industry owing to lack of concentration. At the beginning of the present century dredging operations were commenced in the Irrawaddy and two of its branches in the Myitkyina district, but although the total output reached 9041 ounces in 1909, the venture was recently abandoned. A mine which promised good results was worked for some time at Kyaukpazat in Katha, but in the end failed to prove remunerative.
Gypsum is a soft, white or transparent mineral from which plaster of Paris is made. In the form of scattered transparent flakes it is widely disseminated in the lower Tertiary rocks of the Irrawaddy basin, but is not made use of to any extent. Mixed with cement gypsum confers the property of slow setting.
Iron ores, mostly of lateritic origin, are found and worked on a small scale in many parts of the Province. At Wetwin, near Maymyo, the deposits are comparatively extensive and are being exploited and used for fluxing purposes in the smelting of the Bawdwin silver-lead mines. Similar deposits exist at Twin-ngè.
A mineral very closely resembling jade and known as Jadeite has, for a very long time, been extracted in the form of rounded boulders from a yellow or orange clay at Tawmaw and Hweka, and from river mines at Mamôn on the Uyu, all in the Myitkyina district. It is derived from dykes in serpentine which have been intruded therein under great pressure. The working is still by primitive native methods. The stone is exported in large blocks by way of Mogaung and Kindat where an ad valorem duty is levied, the right of levying being farmed out by Government. The farmer assesses the value of the stone; the owner may either pay duty on the assessment or require the farmer to buy the stone at his own valuation. In 1921, 3815 cwts. of jadeite were extracted. White, green and blood-red varieties are obtained, and most of the output is sold to Chinese who attach magic properties to the stone. The green variety is the best known[1].
The Lead-silver mine of Bawdwin in the Northern Shan States is one of the richest of its kind in the world. Numerous old Chinese workings are to be seen scattered
Fig. 31. Chinese furnaces for the smelting of silver and lead at Bawdwin.
round the neighbourhood, and, according to an old inscription, were being operated as long ago as 1412 A.D., during the Ming dynasty. The extensive lines of entrenchments still to be seen on the heights of the surrounding hills, testify to the tenacity with which these old mines were held against invading Kachins from the north. The ore for the most part consists of a silver-bearing sulphide of lead or galena, containing also a considerable proportion of zinc. The objective of the Chinese smelters seems to have been the silver, for the lead slag was left in heaps to be utilized ultimately by the Company at present working the mine. Between 17½ and 54 ounces of silver to the ton are obtainable from the ore. The ores owe their present home to the compressional movement mentioned in the previous chapter. This movement has produced a zone of fracture, displacement and general disturbance along a north-to-south line passing through Bawdwin. Into this zone of broken rock mineral-bearing solutions have percolated and left their valuable deposits, especially within some decomposed and very ancient volcanic ash beds. The output of refined lead from these mines in 1921 was 33,717 tons, of fine silver 3,555,021 ounces.
Similar old silver-lead mines worked by the Chinese are described as occurring at Bhamo. Ore of this nature is known in the Amherst and Mergui districts, in the Southern Shan States, at Mt Pima in the Yamèthin district, and in the Yônzalin valley near the Salween.
The most valuable mineral Burma possesses is Petroleum, which is found in the Lower Tertiary beds of the Irrawaddy basin on the one side and of the Arakan coast on the other. These beds are, in fact, the "gulf" deposits mentioned in the chapter on Geology, and the formation of petroleum within them, perhaps from some form of vegetation, seems to be connected with the conditions produced by the silting up of the gulf. The desiccation caused the precipitation of gypsum and other sea-water salts, and the saline conditions established are thought by some to have directed the changes taking place in the decomposing vegetation of that period, and to have induced the formation of petroleum instead of lignite or coal. Whatever the original material was, petroleum accumulated in the porous sands of the Miocene period, and was prevented from escaping at the surface by thick caps of impervious clay. Any part of the porous sands not filled with petroleum or with the gas arising therefrom, was filled with water, most of which contained salts such as sodium sulphate, sodium chloride, magnesium sulphate, etc.; the oil being lighter than water would tend to float on the surface of the latter within the sands, and would always take up a higher position than the water unless prevented.
As the folding movement proceeded, these porous beds
32. The Yenangyat Anticline, showing the arch.
with their protecting caps of clay became warped and folded into arches and troughs, the oil finding its way into the crests of the arches and the water occupying the troughs. In some cases the arches were folded so severely as to be fractured, most of the imprisoned oil thereby escaping. In places like Yenangyaung in the Magwe district, on the other hand, the arch is a gentle and undisturbed one, and vast quantities of petroleum have collected in the many porous sandstones beneath it. On this oil is exerted static pressure by the water in the adjacent troughs, so that when the overlying clay-caps are pierced by the drill, the oil is forced up to the surface and frequently 100 or 150 feet into the air. At Singu and Yenangyat, on the Irrawaddy, some distance above Yenangyaung, the arch is not symmetrical as it is in the latter locality, but is much steeper on the eastern side than it is on the western. Two small fields, one in the Upper Chindwin and another at
Fig. 33. Native Oil Well in process of construction.
Minbu on the Irrawaddy, are yielding oil in small quantities. On the Arakan coast the production is more or less negligible. From Burmese crude oil we get petrol, illuminating oil, lubricating oil and wax for candles.
The most famous oil wells are at Yenangyaung, in Magwe. They have attracted the notice of all travellers who passed that way. Symes, who saw them in 1795, writes: "The celebrated wells of petroleum which supply the whole (Burmese) Empire and many parts of India.... The mouth 
Fig. 34. The Yenangyaung Oilfield.
Gems. The greater part of the world's supply of Rubies comes from the Mogôk mines in Upper Burma. A few rubies, sapphires and spinels have been found at Sagyin near Mandalay, and at Nanyazeik in the Myitkyina district. At Mogôk rubies, many of the coveted pigeon-blood colour, accompanied by large quantities of bright red spinel, a few sapphires and occasionally beautiful blue crystals of apatite, are quarried from a gem-bearing gravel occurring at some depth below the alluvial valley floor. The gems are derived from lenticels of crystalline limestone closely associated with basic igneous rocks bands of which are folded up with the ordinary gneiss. Some think the limestone was derived from certain ingredients of the gneiss and was deposited from percolating solutions some time after the deposition or solidification of the gneisses. Others think that they were ordinary sedimentary limestones laid down upon and subsequently folded up with the gneiss. A few gems have been obtained from the limestone itself by driving cuttings into the hill sides or by excavations in fissures or hollows.
The ruby mines at and near Mogôk, some sixty miles north of Mandalay, have been worked by native methods from time immemorial. Cæsar Frederick (1569 A.D.) notes that the king "also is Lord of the Mines of Rubies, sapphires and spinels[3]." The rights of native miners have been preserved. But since 1886, the main work of extraction has been done by a Company with all the aids of science. The present plan is to wash and sift ruby earth (byôn) till all
Fig. 35. Burmese washing for rubies.
foreign matter is eliminated and only rubies and spinels remain.
Salt is manufactured from sea-water and also from the numerous salt springs found in many parts of the country especially in lower Tertiary beds. The Great War gave an impetus to salt extraction, an industry which was discouraged till recently. In 1919, about 70,000 tons were extracted, but in 1921 the output had fallen to 43,000 tons. It is doubtful whether, in normal times, the local produce can compete with foreign salt.
The efflorescence known in India as "reh," which frequently covers the exposed surface of the Tertiary beds, is often found to contain a certain proportion of Carbonate of soda. This impure carbonate, contaminated with sand and mud, is known as "soap-sand" and is used for washing purposes by the Burmans.
Steatite or Soapstone is found in several places in the Arakan Yoma associated with serpentine; the best known mines are in the Minbu district.
The Burma Tin belt of Tenasserim and that of the Federated Malay States are continuous, and together constitute one of the world's greatest tin resources. The ore is the oxide, cassiterite, and is found in the neighbourhood of masses of intrusive granite. The greater part of the ore won comes from alluvial deposits of gravelly clay derived chiefly from the decomposition of the granite.
A fine dark emerald-green Tourmaline is mined to a small extent at Namôn in Karenni, and pink, brown or black types are obtained at Maingnin in Mongmit. The pink variety known as Rubellite is also obtained from the ruby mines.
Tungsten in the form of the oxide, Wolfram, has been mined in both Tavoy and Mergui during the past ten years or so, and is found also in Southern Shan States, Karenni, and Thatôn. Like tin it is closely connected with granite and is found in the many quartz veins which traverse this granite and the ancient sediments into which the latter has been intruded. The chief use to which tungsten is put is that of hardening steel. It differs from other hardening agents such as chromium, vanadium, etc., in that scarcely any diminution of hardness results from a rise in temperature. For this reason it is an invaluable constituent of the steel required for high-speed tools, which preserve their cutting capacity in spite of the high temperature caused by friction. The demand occasioned by the war greatly stimulated wolfram mining. In 1918—19, the out-turn amounted to 4443 tons.