Warta Geologi, Vol. 52, No. 2, August 2026, pp. 53-63
Ahmad Izzat Zolkefli1, Khairul Nazri Hj Yaakub2, Abdul Hadi Abdul Rahman3, Mahat Sibon4, Fakhruddin Afif Fauzi5,*, John Joseph Jinap1, Shari Ismail6, Yusari Basiran3
1Department of Mineral and Geoscience Malaysia Sarawak, Jln Wan Abdul Rahman, Kenyalang Park, 93712 Kuching, Sarawak, Malaysia
2Department of Mineral and Geoscience Malaysia Terengganu, PT3102K, Jln Sultan Sulaiman, 20200 Kuala Terengganu, Terengganu, Malaysia
3Department of Mineral and Geoscience Malaysia Headquarters, Level 9, Menara PjH, Jln Tun Abdul Razak, Precinct 2, 62100 Putrajaya, Malaysia
4Department of Mineral and Geoscience Malaysia Perak, Jln Sultan Azlan Shah, 31400 Ipoh, Perak, Malaysia
5Department of Mineral and Geoscience Malaysia Kedah / Perlis / P.Pinang, Jln Perak, Seberang Jalan Putra, 05150 Alor Setar, Kedah, Malaysia
6Department of Mineral and Geoscience Malaysia Pahang, Jln IM 4/1, Bandar Indera Mahkota, 25604 Kuantan, Pahang, Malaysia
*Corresponding author email address: afif@jmg.gov.my
Abstract: The ion-adsorption clay type rare earth elements deposit (IAC-REE) is recognised as one of Malaysia’s strategic mineral resources due to its high global demand and economic potential. REEs are important raw materials for advanced sectors such as electronics, green technology, defence, catalysis, and automotive manufacturing. As IAC-REE exploration in Malaysia is relatively new and not yet well understood, the Department of Mineral and Geoscience Malaysia (JMG) has developed guidelines to assist its officers with the fundamentals of exploration and the interpretation of laboratory results. JMG has published two editions of these guidelines. The first edition, published in 2015, provides an overview of REE genesis and global deposit types, along with a step-by-step approach to conducting reconnaissance surveys. The second edition, published in 2023, is an updated version that focuses more on the genesis of IAC-REE deposits, provides guidance for subsequent exploration, and includes methods for calculating resources, while also addressing in-situ leaching (ISL) method and environmental concerns associated with irresponsible REE mining. These guidelines are based on reputable local and international journals and research studies. This paper aims to outline the contents of the second edition of the guidelines and highlight their relevance to the IAC-REE exploration conducted by JMG.
Keywords: Rare earth elements, ion adsorption clay, exploration guidelines, in-situ leaching, Malaysia
Abstrak: Endapan unsur nadir bumi jenis lempung jerapan ion (IAC-REE) diiktiraf sebagai salah satu mineral strategik Malaysia kerana permintaan global yang tinggi dan potensi ekonominya. REE merupakan bahan mentah penting dalam sektor berteknologi tinggi seperti elektronik, teknologi hijau, pertahanan, pemangkin, dan pembuatan automotif. Memandangkan penerokaan IAC-REE di Malaysia masih baharu dan kurang difahami, Jabatan Mineral dan Geosains Malaysia (JMG) telah membangunkan garis panduan bagi membantu pegawai-pegawai geosains memahami asas-asas aktiviti penerokaan dan tafsiran hasil makmal. JMG telah menerbitkan dua edisi garis panduan ini. Edisi pertama yang diterbitkan pada tahun 2015 merangkumi pengenalan kepada genesis REE dan jenis-jenis endapan di peringkat global, serta pendekatan langkah demi langkah untuk menjalankan tinjauan peninjauan awal. Edisi kedua, diterbitkan pada tahun 2023, merupakan versi terkini yang memberi fokus lebih mendalam kepada genesis endapan IAC-REE, panduan untuk kerja susulan penerokaan, serta kaedah pengiraan sumber. Ia turut merangkumi penerangan tentang kaedah perlombongan larut resap setempat (ISL) dan isu alam sekitar berkaitan perlombongan REE yang tidak bertanggungjawab. Garis panduan ini dibangunkan berdasarkan jurnal dan kajian penyelidikan tempatan serta antarabangsa yang berwibawa. Justeru, kertas kerja ini bertujuan menghuraikan kandungan edisi kedua garis panduan ini dan mengetengahkan kepentingannya dalam konteks penerokaan IAC-REE oleh JMG.
Kata kunci: Unsur nadir bumi, lempung jerapan ion, garis panduan eksplorasi, larut resap setempat, Malaysia
References:
Aubert, D., Stille, P., & Probst, A., 2000. REE fractionation during granite weathering and removal by waters and suspended loads: Sr and Nd Isotopic Evidence. Geochimica et Cosmochimica Acta, 65(3), 387-406. Doi: 10.1016/ S0016-7037(00)00546-9.
Banfield, J.F., & Eggleton, R.A., 1989. Apatite replacement and Rare Earth Mobilization, Fractionation and Fixation during weathering. Clay and Clay Minerals, 37, 113-127. Doi: 10.1346/CCMN.1989.0370202.
Bao, Z., & Zhao, Z., 2008. Geochemistry of mineralization with exchangeable REY in the weathering crusts of granitic rocks in South China. Ore Geology Reviews, 33, 519-535. Doi: 10.1016/j.oregeorev.2007.03.005.
Braun, J-J., Pagel, M., Muller, J-P., Bilong, P., Michard, A., & Guillet, B., 1990. Cerium anomalies in lateritic profiles. Geochimica et Cosmochimica Acta, 54, 781-795. Doi: 10.1016/0016-7037(90)90373-S.
Compton, J.S., White, R.A., & Smith, M., 2003. Rare earth element behaviour in soil and salt pan sediments of a semi-arid granitic terrain in the Western Cape, South Africa. Chemical Geology, 201, 239-255. Doi: 10.1016/S0009- 2541(03)00239-0.
Han, K.N., 2020. Characteristics of precipitation of rare earth elements with various precipitants. Minerals, 10(20), 178. Doi: 10.3390/min10020178.
Imai, A., Senematsu, K., Ishida, S., Watanabe, K., & Boosayasak, J., 2008. Rare earth elements in weathered crust in Sn-bearing granitic rocks in Southern Thailand. Proceeding of the International Symposia on Geoscience Resources and Environments of Asian Terranes (GREAT 2008), 4th IGCP 516 and 5th APSEG; November 24-26, 2008, Bangkok, Thailand.
JMG, 2015. Garis panduan eksplorasi unsur nadir bumi (Guidelines of rare earth elements, JMG.GP.20). Department of Mineral and Geoscience Malaysia, Putrajaya. 69 p.
JMG, 2023. Garis panduan eksplorasi unsur nadir bumi, edisi kedua (Guidelines of rare earth elements, second edition, JMG.GP.20). Department of Mineral and Geoscience Malaysia, Putrajaya. 92 p.
Kanazawa, T., & Kamitani, M., 2006. Rare earth minerals and resources in the World. Journal of Alloys and Compounds, 408-412(2006), 1339-1343. Doi: 10.1016/j. jallcom.2005.04.033.
Li, M.Y.H. & Zhou, M-F., 2020. The role of clay minerals in formation of the regolith hosted heavy rare earth element deposits. American Mineralogist, 105, 92-108. Doi: 10.2138/ am-2020-7061.
Li, M.Y.H., Zhou, M.-F. & Williams-Jones, A.E., 2019. The genesis of regolith hosted heavy rare earth element deposits: Insights from the world-class Zudong deposit in Jiangxi Province, South China. Economic Geology, 114, 541–568. Doi: 10.5382/econgeo.4642.
Li, Y.H.M., Zhao, W.W. & Zhou, M.-F., 2017. Nature of parent rocks, mineralization styles and ore genesis of regolith-hosted REE deposits in South China: An integrated genetic model. Journal of Asian Earth Sciences, 148, 65-95. Doi: 10.1016/j.jseaes.2017.08.004.
Nawab, A., Yang, X. & Honaker, R., 2022. Parametric study and speciation analysis of rare earth precipitation using oxalic acid in a chloride solution system. Minerals Engineering, 176, 107352. Doi: 10.1016/j.mineng.2021.107352.
Papoulis, D., Tsolis-Katagas, P. & Katagas, C., 2004a. Progressive stages in the formation of kaolin minerals of different morphologies in the weathering of plagioclase. Clays and Clay Minerals, 52, 275-286. Doi: 10.1346/ CCMN.2004.0520303.
Papoulis, D., Tsolis-Katagas, P. & Katagas, C., 2004b. Monazite alteration mechanisms and depletion measurements in kaolins. Applied Clay Science, 24, 271-285. Doi: 10.1016/j. clay.2003.08.011.
Sanematsu, K., & Kon, Y., 2013. Geochemical characteristics determined by multiple extraction from ion-adsorption type REE ores in Dingnan County of Jiangxi Province, South China. Bulletin of the Geological Survey of Japan, 64(11/12), 313-330.
Sanematsu, K., Kon, Y., Imai, A., Watanabe, K., & Watanabe, Y., 2013. Geochemical and mineralogical characteristics of ion-adsorption Type REE mineralization in Phuket, Thailand. Miner Deposita, 48, 437-451. Doi: 10.1007/ s00126-011-0380-5.
Sun, S-S. & McDonough, W.F., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle. Geological Society, London, Special Publications, 42, 313- 345. Doi: 10.1144/GSL.SP.1989.042.01.1.
Ubaidillah, A.S., Ismail, H., Endut, Z. & Aminuddin, M.I.K.A., 2024. Characterization of ion-adsorption clay rare earth elements (REEs) in weathered granite rock in North- Western area of Pahang state, Malaysia. IOP Conf. Ser.: Earth Environ. Sci., 1422, 012018. Doi: 10.1088/1755- 1315/1422/1/012018.
Verplanck, P.L., 2017. The role of fluids in the formation of rare earth deposits. Procedia Earth and Planetary Science, 17, 758-761. Doi: 10.1016/j.proeps.2017.01.014.
Voßenkaul, D., Stoltz, N.B., Meyer, F.M. & Friedrich, B., 2015. Extraction of rare earth elements from non-Chinese ion adsorption clays. European Metallurgical Conference; Düsseldorf. Doi: 10.13140/RG.2.1.1177.6401.
Yaraghi, A., Ariffin, K.S. & Baharun, N., 2020. Comparison of characteristics and geochemical behaviours of REEs in two weathered granitic profiles generated from metamictized bedrocks in Western Peninsular Malaysia. Journal of Asian Earth Sciences, 199, 104385. Doi: 10.1016/j. jseaes.2020.104385.
Manuscript received 21 June 2025;
Received in revised form 20 October 2025;
Accepted 1 April 2026
Available online 30 August 2026
DOI: https://doi.org/10.7186/wg522202601
0126-5539; 2682-7549 / Published by the Geological Society of Malaysia.
© 2026 by the Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC-BY) License 4.0
