Sungei Besi, Hong Fatt
New & Recent International |
Click on image for details.
The now abandoned and rehabilitated Sungei Besi alluvial tin deposit was located on the southeastern outskirts of Kuala Lumpur, in the Federal Territory of Kuala Lumpur and neighbouring Selangor State (#Location: 3° 2' 5"N, 101° 42' 43"E).
Before closure in the mid-1980's, the Sungei Besi operation was owned by Sungei Besi Mines Limited, which was controlled by the Malaysian Mining Corporation (MMC), and was managed by Pernes Charter Management Co. MMC was 71% owned by the Malaysian Government and 20% by Charter Consolidated. Pernes Charter Management was controlled 50% by Charter Consolidated and 50% by the Malaysian Government.
The Sungei Besi Mine was a dry mining open cut alluvial tin operation. Tin had been exploited near Sungei Besi since 900 AD, when Arabs are known to have traded for tin in the area. During the thirteenth century, Thais commenced mining in the district, and in the eighteenth century, Chinese had began mining at Sungei Besi. By around 1911 the British formed Sungei Besi Mines Limited to exploit the deposits.
During the Second World War the Japanese operated the mine. In the mid 1950's Chinese miners ceased mining at the famous Hong Fatt Mine, which became part of the Sungei Besi open cut No. 2. In the late 1960's Sungei Besi Mines Limited was taken over by Charter Consolidated and towards the end of 1977 passed under the control of the newly formed Malaysian Mining Corporation.
The mine was visited in January, 1978, and observations from the visit and discussions with geologists working on the deposit are included below.
See the separate West Coast Malaysia Tin Belt record.
Bedrock is principally composed of limestone and granite, although Procter (1955) also recorded shale, breccia and "grey-schist" in the bedrock. The granite is a medium- to coarse-grained muscovite variety, occasionally containing some tourmaline and is of probable Middle Triassic age. It outcrops in the eastern part of the area, and is mostly strongly weathered. Thin (~30 cm thick) dykes of fine-grained muscovite granite, aplite and tourmaline-aplite are also encountered, usually intruding along faults in the limestone.
The limestone is generally recrystallised, medium- to coarse-grained, blocky to well bedded, and is composed almost entirely of marble with few impurities. It is usually grey or rarely pinkish-grey in colour, sometimes containing thin black bands of carbonaceous material. Bedding varies from a few, up to 50 cm in thickness, averaging about 20 cm, dipping moderately to the west at ~35° and striking north-south parallel to the granite contact. The limestone is exposed at surface or below Quaternary alluvium cover as either a flat platform, breached by shallow potholes of ~30 to 60 cm diameter, or as jagged pinnacles with concordant tops that are at ~38 mas. These pinnacles may protrude up to 30 m into the alluvium over a plan area of 100 x 50 m2 or less. Limestone pinnacles often form the margins of larger potholes with diameters of from 3 to 10 m and depths of 10 m that have smooth vertical or steeply inclined walls. This limestone has been correlated with the geologically and geomorphically similar Silurian Kuala Lumpur Limestone (Gobbett, 1964). The contact between the limestone and the granite is taken to be faulted, striking ~north-south.
Only very minor exposures of the limestone are seen at the surface, as it is masked by a ~900 m wide strip of thick Quaternary alluvium. To the west, this alluvium laps onto the possibly Carboniferous to Permian (or Triassic?) Kenny Hill Formation quartzites, which include inter-bedded shales and mudstones, and unconformably overlies the Kuala Lumpur Limestone.
To the SE of the mine, the Kuala Lumpur Limestone is unconformably overlain by the Kajang Formation on its eastern margin. This formation, which is cut by the main granite batholith to the north, unconformably overlies the Kenny Hill Formation away from the mine area.
The mineralised alluvium at Sungei Besi predominantly comprises granitic sand localised within a deep depression formed in the limestone along its contact with the granitic batholith. This depression is interpreted to have originally been a river valley, later filled by material washed in from the granitic margin rather than from along the valley. The trough varies from 100 to 600 or 700 m in width and extends over a distance of around 3.5 km. At its deepest, the elevation difference between the lip and the base of the depression (at Hong Fatt) is 132 m.
Quaternary sediments are well stratified, generally horizontal, and composed of consolidated and unconsolidated, grey or brown muddy sand and sandy mud, dark brown or black muddy or sandy peat, white or brown clay, and gravel. Some strata are gently dipping, from 5 to 20°. In some of the larger potholes, the Quaternary strata are concordant with pothole walls, suggesting that karstic solution occured after deposition of the strata. The maximum thickness of these sediments exposed above bedrock varies from as little as 5, to >100 m, the bulk of which is sand, with mud, peat and clay next in abundance and gravel occurring rarely. All these sediments are interstratified and no one is restricted to any definite stratigraphic level, although the lowest layer in the limestone potholes is usually a tight clay, overlain by considerable amounts of carbonised plant fragments. The nature of the various facies may be summarised as follows, after Ayob (1970):
Sand, which are grey or light to dark brown in colour, and well stratified with beds that are generally between 0.15 and 2 m thick. Almost all of the sands contain from 5, up to as much as 40% mud. When it contains >10% mud, the sand is generally hard and reasonably indurated, and loosely compacted with lesser mud. The latter is common in the upper stratigraphic horizons, whilst the former is more prevalent in the lower stratigraphic horizons. Brown and dark brown sand beds usually contain up to 10 wt.% organic material, chiefly carbonised plant fragments Ayob (1970).
The sand beds are mainly fine to medium-grained, moderately to very poorly sorted, and unimodal. The largest grains are commonly between 2 and 5 mm, but rarely contain pebbles up to 5 cm in diameter. In many of the sand beds, which are most commonly 15 to 30 cm thick, the coarsest grains are restricted to the lower part of the bed, fining upwards. The sand-sized and coarser grains are composed of ~75 to 85 % quartz and 5 to 10% muscovite, with the remainder being tourmaline, pyrite, cassiterite, zircon, chlorite and iron oxides. The quartz grains are angular to sub-angular and contain microlites, mineral inclusions and liquid and gaseous vacuoles. Tourmaline grains are generally sub-idiomorphic and include two varieties, a blown to dark brown variety which predominates, and a bluish white variety Ayob (1970).
Where sighted during the visit, the mineralised alluvium was fine to medium grained, yellow white to pink tinged quartz-feldspar sand with a grain size generally of ~1 mm, and in places locally up to 2 mm, with occasional 5 x 10 x 5 mm quartz pebbles. The sand was ~50:50 quartz and feldspar. The feldspar was cream to grey and not strongly decomposed. There are generally no cobbles within the sand, although very occasionally 1 to 2 cm thick pebble bands with quartz pebbles around 1 cm in diameter were obvious. In detail there was no stratification to the sand, although pinkish layers from 0.2 to 1 m thick are obvious dipping at ~45° W, away from the granite contact.
Mud beds are well stratified, and vary in colour, depending on the content of carbonised plant fragments, from grey when there is little or none, to greyish-brown, or dark brown when containing a considerable amount, which may be as much as 15 wt.%. They are generally hard and consolidated, although some are loose and friable when they contain >10 wt.% carbonised plant fragments. The mud beds are also sandy, commonly containing up to 30 % sand. The coarsest grains are usually sand-sized, and are rarely granules of as much as 3 to 4 mm in diameter. Thick (3 to 5 m) homogeneous, and very poorly sorted and bimodal grey or bluish white mud beds also occur, which have little or no calbonised plant fragments, and contain small pebbles as their largest grains. The sand grains are angular to sub-angular and are composed mainly of quartz and muscovite, with some cassiterite and pyrite.
Peat and organic remains - organic material occurs as lignite deposits and muddy or sandy peat. The lignite is black and occurs as lenses or as unstratified accumulations, usually containing some sand. Peat is generally brown to dark brown or black, fairly friable and is usually well stratified with beds varying from about 0.15 to 1 m thick, largely composed of carbonised bark, leaves, twigs, stems and roots of large plants. Plant fragments are bound in a matrix of fine-grained sand and mud, and occur in various stages of carbonisation, commonly in the sand, mud and peat strata. They usually comprise brown to dark brown pieces of bark, twigs and logs with diameters commonly of ~10 cm. Examples with girths up to 1.5 m also occur, some of which were probably preserved in growing position as they are upright and penetrate bedding planes.
Clay beds are also generally well stratified, compact, soft and plastic with thicknesses of 15 to 30 cm. Most are whitish-grey, although some may be light brown or brown when containing fine carbonaceous particles. They are composed almost entirely of very fine grained clay minerals, probably predominantly kaolinite, with very little or no silt and larger grains, and are common higher in the stratigraphy.
Gravel, usually occurs as lenses in the sand and mud strata and rarely form definite beds. It is generally loose, very poorly sorted and mainly comprise sub-rounded pebbles of quartz and granite and angular sand-sized quartz, tourmaline, pyrite and cassiterite grains all bound in a matrix of white clay. Much of this clay is probably a product of in situ weathering of other minerals. The largest clasts are about 8 to 10 cm in size, predominantly quartz.
In the centre of the southern section of the No. 2 open pit, the site of the old Hong Fatt Mine, a total thickness of 132 m of commercially extractable alluvium was developed.
Cassiterite is in general greater than 0.3 mm in diameter, but is only obvious to the inexperienced eye in high grade patches where it occurs as wisps or patches of brown to black grains from 0.5 to 1 mm in diameter. In places, similar wisps of fine tourmaline are also found.
The bedrock limestone is apparently completely barren, while the granite carries an average of 3 to 5 ppm Sn. However, within the granite on the eastern margin of the No. 2 pit, a number of extremely rich cassiterite pods were found within the granite, and these and others like them are assumed to be the source of the cassiterite in the wash. Boulders in the mine office comprised:
• Massive coarse grained (2 to 4 mm across) crystalline cassiterite with 10 to 20% limonite, possibly after pyrite;
• Massive clear quartz with up to 20% fine brown cassiterite;
• White quartz with coarse cassiterite blebs.
The larger of these pods are said to have yielded up to 100 tonnes of cassiterite.
In 1978, the two main pits at Sungei Besi were the No. 1 and No. 2. The No. 1 pit was some 1000 x 500 m at the surface, elongated north-south along the granite contact. Immediately to the south, the No. 2 pit which was of the order of 1500 x 900 m.
Production statistics are as follows for the twelve month period ending 31st March 1977.
• Total ore mined and treated - 1 890 850 m3
• Total waste mined & dumped - 1 896 358 m3
• Total mined - 3 787 208 m3
No. 2 pit @ 660 g/m3 - 748 tonnes SnO2 concentrate,
No. 3/5 pit @ 1070 g/m3 - 696 tonnes SnO2 concentrate,
No. 5 pit @ 380 g/m3 - 53 tonnes SnO2 concentrate,
Total Production: - 1497 tonnes SnO2 concentrate = 1094 tonnes of contained Sn.
The most recent source geological information used to prepare this summary was dated: 1978.
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd. Unauthorised copying, reproduction, storage or dissemination prohibited.
Sungei Besi - Hong Fatt
Top | Search Again | PGC Home | Terms & Conditions