Sains Malaysiana 30: 69-75 (2001)                                                                                                     Sains Bumi /

Earth Sciences

Slag Fragments in Heavy Mineral Concentrates

from Bakri Area, Johor

Wan Fuad Wan Hassan

Program Geologi

Pusat Pengajian Sains Sekitaran dan Sumber Alam

Fakulti Sains dan Teknologi

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E, Malaysia

ABSTRACT

This article describes the occurrence of slag fragments from the Bakri area, Johor. The slag occurring as traces in forms of minute spheres, tubes, rods and angular fragments were recovered together with heavy mineral fractions from stream sediments and old mine collections. Polished section study of the slag shows the presence of magnetite mineral and some tin metal surrounded by glassy matrix. Magnetite, the main phase, has textures ranging from euhedral to angular grains and skeletal growth. The skeletal growth texture and shapes of the slag grains such as rods indicate sudden cooling by being poured out from a melt, as is being carried out in a smelting plant. The presence of these slag traces suggest that tin smelting on a small scale was carried out in the vicinity of the present Bakri town by the old generation tin miners, possibly before the coming of the British to Malaya.

ABSTRAK

Makalah ini membincangkan kewujudan serpihan sanga dari kawasan Bakri, Johor. Sanga di situ wujud dalam bentuk sfera seni, tiub, rod dan serpihan bersegi ditemui bersama mineral berat dalam sedimen sungai dan koleksi daripada lombong lama. Kajian irisan gilap menunjukkan kehadiran mineral magnetit dan sedikit logam timah dikelilingi matriks kekaca. Magnetit sebagai fasa utama mempunyai tekstur dari butiran euhedron, bersegi hingga rerangka. Tekstur rerangka dan bentuk butiran sanga seperti rod mencadangkan penyejukan mendadak seperti apabila dicurah keluar daripada leburan. Kehadiran surihan sangat mencadangkan kerja peleburan timah secara kecil­-kecilan telah dilakukan di sekitar kawasan yang sekarang dikenali sebagai Bakri oleh pelombong angkatan terdahulu, mungkin sebelum kedatangan orang British ke Malaya.

RUJUKAN/REFERENCES

Edwards, A. B. 1965. Textures of the are minerals. Melbourne: The Australian Institute of Mining and Metallurgy.

Kassim Ahmad. 1960. Kisah Pelayaran Abdullah. Kuala Lumpur: Fajar Bakti Sdn. Bhd.

Mohammad Nazri Tamby. 2000. Geologi pegmatit dan mineral berat kolumbit-tantalit di Bukit Mor, Muar, Johor. Disertasi Ijazah Sarjanamuda Sains, Program Geologi, Universiti Kebangsaan Malaysia.

Tan Kuan Yaw. 2000. Geologi, permineralan, pegmatit dan pemetaan terperinci kawasan Bukit Dinding dan Bukit Nyior Tunggal, Bakri, Muar, Johor. Disertasi Ijazah Sarjanamuda Sains, Program Geologi, Universiti Kebangsaan Malaysia.

Vallentine, E. J. 1913. The romances of a Malayan tin field. The Mining Journal, London. An article in Raffles Library, Reference Q-II: 202.

Wan Fuad Wan Hassan. 1982. Aspects of geochemistry and mineralogy of tin and associated minerals in the Malaysian tin fields. PhD thesis, University of Leeds.

Williams, H., Turner, F.J. & Gilbert. C. 1954. Petrography. San Francisco: W. H. Freeman and Company Inc.