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the alluvium in the bank of the Ib and its tributaries, the Maini and the Sonajori. This gravel bed had been exploited by shafts and open cuts usually located on the banks of the rivers or at some distance from them. Evidences of old placer mining are abundant in the area. But as a considerable time has elapsed since the mines were worked, the pits have caved in and become filled up to such an extent that it was impossible to examine a section of the gravel bed. At a few points, however, where the gravel bed is exposed in the valley of the Ib, it is seen to rest on a gneissic platform at a depth of 15 to 20 ft. and to have a thickness of 1 to 11 ft. The gravels mostly consist of well rounded pebbles of vein quartz, tourmaline-quartz rock, tourmaline, etc., in à clayey matrix.
The mining was in progress during the past century but was suddenly suspended by the State sometime in the late eighties, owing, it is said, to accidents in the mines and also because of the smuggling out of the State of the metal won. At present, no digging of any kind for gold is allowed. The only yold now obtained comes from the washing of the river sands and the soil mantle on the stream banks and on the divides between the nalas. The experience of generations of gold-washers has enabled them to locate the spots where their operations would be most paying. Gold-washing is carried on mainly during the rainy season ; at other times it is practised only casually after heavy showers.
The gold thus obtained consists mostly of small flattened particles of bright yellow colour showing no tarnished or black coating. Individual particles are spongy and a few show under a powerful lens minute particles of quartz attached to them. Although the corners of a great many particles have been somewhat rounded, they do not in general appear to have been transported far from their place of origin. About 30-50 tolas of gold are won annually. This amount is purchased by the State in exchange for rice.
The average earnings of the gold-washers are exceedingly small; they, therefore, combine this pursuit with other occupations.
From the abundance of ancient workings, it should not, however, be supposed that the placers in the State have been worked out. There are areas on the bank of the Ib which have not been exploited to any considerable extent. The placers in such areas are shallow and there would not be any special difficulties in working
The pay gravel may be found in depth underneath the alluvium at other places.
From the physical characters of the gold and from the distribution of the auriferous alluvium Dr. Dey is led to believe that the gold has been derived from the quartz veins which are so abundant in the area. The quartz veins have not been prospected as yet. A study of these veins appears necessary, as this would not only help to locate the probable areas in which placer deposits may be expected but they might themselves possess a gold value high enough to warrant development.
It is hoped that during the ensuing field season suitable prospecting operations will be undertaken in order to indicate the economic possibilities of these gravels. As the auriferous gravel deposit is usually shallow, the operation of prospecting by means of a number of trial pits will not be expensive. The overlying alluvium is soft and easily removable. The pits should, according to Dr. Dey, be sunk to the solid bed-rock as the underlying gneiss is known to carry gold on its decomposed surface.
74. On the north side of the Mogok · massif Katha district and Mongniit State, Burma.
illicit gold workings were noted by Mr. Clegg
at the following places (1) One mile south-east by south of Pinkan in a tributary of
Maunggwe chaung (23° 5': 96° 10'). (2) Paungsho chaung from the Twinnge-Mongmit Road to its
confluence with Kadan chaung (23° 5' : 96° 12') to
(23° 7' : 96° 14'). (3) Nansit chaung (23° 5': 96° 14'). (4) Shwegyin chaung one mile south of Kyaukmaw (23° 5':
96° 0'). (5) One and a quarter miles north-east by north of Webaung.
In every case where working was going on the gold was obtained from stream gravels which were in most cases rather sparse. The area on Shwegyin chaung is the most extensive and occurs where the stream debouches into a jungle-covered plain composed of soil cap, gravels and calcareous tufa. The cementing effect of the latter and the changing of the stream course owing to the formation of travertine dams, does not encourage the hope of large quantities of gravel available for easy washing. The local
inhabitants report that before work was stopped by the Forest Department, earnings had been from Rs. 5 to Rs. 8 per day, per team of three men.
In Paungsho chaung active washing was being carried out by small parties of local villagers. The gold is coarse and rather angular and runs in grains up to more than a millimetre in diameter. Bamboo pumps are used for dewatering the pits excavated for the gravel and in all cases seen the washing procedure was the same.
The gravel is placed in a rocking basket at the top of a launder about five feet long and with three-inch
three-inch riffles. When a consignment of twenty baskets of gravel has passed over the launder the residue from the riffles is washed into a wooden pan for final separation. In this chaung the gravels are neither extensive nor thick.
In the tributary of Maunggwe chaung one mile south of Pinkan the bed of the stream is very bouldery and the gravels which occur between the boulders are sparse.
Nevertheless the local villagers reported that they were able to wash about eight annas worth of gold per day in the rains. Just above the most southerly of the pits a vein of iron pyrites crosses the chaung but no gold has been detected in samples of it.
The occurrences are not of sufficient promise to attract capital and the amounts of gold produced not of sufficient quantity to warrant specific Government interference.
Graphite. 75. Flaky graphite was noted in granitic schists near Bora Konde
sanvali (18° 31': 81° 14'), and two miles Bastar State, Eastern south west of Kamaram (18° 25' : 81° 12'). States Agency
The occurrences are not likely to be of any economic importance.
76. Graphite was noted by Mr. Clegg in a quartz vein in the calciphyres just over a quarter of a mile south-east of Tawyokyaung,
Mandalay district (22° 19' : 96° 4'). The vein Mandalay district, is about five feet thick and dips east at 20°. Burma.
Attempts have been made to prospect it and an adit has been driven down the vein for about 20 yards. The graphite is impure and is of the nature of a graphite-quartz schist Small flakes of graphite together with crystals of spinel and phlogopite characterise the contiguous calciphyres. The occurrence is not of economic importance.
Iron-ore. 77. Mr. Crookshank reports cliffs extending for 24 miles, of almost pure iron-ore at the top of the Bailadila ridge on the western side
east of Kondapal (18° 50' : 81° 11'). As these Bastar State, Eastern States Agency.
deposits have never been opened up it is
impossible to estimate the quantity of ore present, but it must amount to many millions of tons. Patches of good iron-ore are common in the laterite which caps the ridge, but it would be impossible to say whether it is of good enough quality to be of economic importance without extensive sampling. One large deposit of almost pure hematite forms a considerable hill at point 3760 in the middle of the laterite plateau.
78. Mr. A. B. Dutt notes that boulders of magnetic iron-ore (magnetite) occur in association with hornblende granite at the bend
of the Panlaung river about half a mile E. Yengan State, Burma.
S. E. of Nyaunggyat (21° 6' : 96° 21'), Yengan State.
The ore is good but the quantity is indefinite, transport is difficult and it is probable that the deposit will never be worked, except by local Shan iron-smelters.
79. Magnetite in fairly big crystals but in small quantity is also reported by Mr. Dutt to occur in granite-pegmatites in the hills
about three miles E. N. E. of Lethagon (21° Meiktila district, Burma.
l': 96° 12'), Meiktila district, and in lumps in pegmatitic granite in the hills about three and a half miles E. N. E. of Myaingtha (20° 52' : 96° 13'), Meiktila district. The two latter occurrences are only of academic importance.
80. Quartz veins with galena have been noticed in the laminated shales at Karamtara (20° 41': 80° 48') in Ambagarh Chauki zamin
dari close to the junction of the shale with Drug district, Central the granite and porphyry.
the granite and porphyry. These are similar Provinces.
to the occurrences recorded last year further south at Thelkadand (20° 37': 80° 45') in the Panabaras zamin
Evidences of further prospecting works, with disappointing results, have been observed at Thelkadand this year.
81. Dr. Dey found traces of galena in the fault Jashpur State, East- rock, 1 mile north of Singibahal (22° 33' : ern States Agency.
84° 0') and Phar.bahar (22° 25' : 83° 55'). 82. Mr. J. B. Auden states that occasional pebbles of galena and pyrites are found in the nala about 550 yards W. S. W. of hill
4432 near Lhetta (30°35': 77° 48'). The Dehra Dun district, U. P.
country rocks are sheared and contorted Chand
pur phyllites, subject to landslides. No lode was located. It is unlikely that any extensive mineralisation has taken place.
83. Instances of yellow and brown och reous enrichments have frequently been noticed in the ferruginous shales of the Sanjari tahsil
of Drug district. Both yellow and brown Drug district, Central Provinces,
types have been met with. These are often
quite soft and fairly free from gritty matter and may be of use
as pigments. The ferruginous shales southeast of Kamkapar (20° 41': 80° 54') are particularly rich in ochreous material.
84. Dr. A. L. Coulson noted occasional pits in the decomposed upper portions of the Panjal trap forming the Poshkar ridge (31°
2': 74° 30') in the Baramula tahsil of the Baramula
district, Baramula district, Kashmir, where the indigeKashmir.
nous workers had apparently worked ochres for local use.
None of that seen was worth collecting. .
Petroleum. 85. Charge of the office of Resident Geologist, Burma Geological Department, Yenangyaung, was held by Mr. E. J. Bradshaw throughout 1937. Besides advising on technical matters arising out of the administration of the oil-fields and on problems relating to leasing and development, the Resident Geologist was consulted on the drafting of the revised General Orders of the Warden, Burma Oil-Fields, made under the Rules under the Burma Oil-Fields Act, 1918.
1 Rec. Geol. Surv. Ind., 72, Pt. 1, p. 53, (1937).