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"The epithermal Arinem veins system of gold-silver-base metal mineralization is located in the Arinem area in the southwestern part of Java Island, Indonesia. The veins are composed predominantly of quartz+calcite±illite±kaolinite with variable amount of manganese oxide and limonite and high amount of sulfides. The deposit contains a number of Tebearing minerals, notably tellurides and tellurosulfide minerals. The tellurium mineral assemblages in the Arinem and Bantarhuni veins are similar in the presence of hessite (Ag Te), petzite (Ag AuTe ), stutzite (Ag Te ), tetradymite (Bi Te S) 2 3 2 5 3 2 2 dan altaite (PbTe). The tellurium mineral assemblages vary from sample to sample and most of the observed telluride occurrences consist of at least 2 different phases (e.g. petzite-hessite, tetradymite-hessite, petzite-hessite-altaite). Gold concentrations measured in Te-mineral of petzite from the Arinem vein are in the range between 14.24 to 18.32 wt%. Some hessite and stutzite contain gold up to 3.48 and 1.10 wt%, respectively. Some of electrums are present as inclusions in Te-mineral patches in both veins."

"Adanya peraturan baru mengenai pelaksanaan kewajiban peningkatan nilai tambah menimbulkan suatu fenomena pro dan kontra, selain itu terdapat resistensi dari kalangan pengusaha mengenai besaran tarif Bea Keluar untuk ekspor produk mineral hasil pengolahan. Tujuan penelitian ini adalah untuk mengetahui formulasi kebijakan tarif Bea Keluar untuk ekspor produk mineral hasil pengolahan dan pelaksanaan peraturan mengenai peningkatan nilai tambah ekspor mineral hasil pengolahan dan pemurnian. Konsep yang digunakan dalam penelitian ini adalah konsep formulasi kebijakan publik. Penelitian ini menggunakan pendekatan kualitatif dengan jenis penelitian deskriptif dengan wawancara mendalam. Hasil penelitian menunjukkan bahwa formulasi kebijakan tarif Bea Keluar untuk ekspor produk mineral hasil pengolahan dibutuhkan untuk melindungi kepentingan nasional. Peraturan yang mengatur ekspor mineral hasil pengolahan dan pemurnian sudah berlaku, namun belum ada kegiatan ekspor yang terjadi yang disebabkan oleh persyaratan ekspor mineral yang belum dipenuhi oleh pengusaha pertambangan mineral.

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A new increasing value-added minerals implementing regulations gives rise around phenomenon of the pro and contra and resistence from the mining corporations regarding the export duties tariff on processed mineral products. The purpose of this study is to determine the export duty tariff for processed mineral products policy formulation and implementation of its regulations. Concept used in this study is the concept of public policy formulation. This study applies qualitative with descriptive approach which use in-depth interviews. Result indicates that export duties on processed minerals is necessary in terms of protecting national interests. Regulation on processed minerals has been applied though no export activities happening recently due to lack of requirements and act of resistance from mining corporations."

"Zeolit NaY berbasis mineral alam berhasil disintesis dari zeolit alam Bayat Klaten dan kaolin Bangka sebagai sumber alumina dan silikanya. Zeolit NaY disintesis setelah material sintesisnya: zeolit alam Bayat Klaten dan kaolin Bangka di pretreatment terlebih dahulu dengan perlakuan : aktivasi, purifikasi, fragmentasi untuk zeolit alam Bayat, dan ekstraksi silika dari kaolin Bangka. Kemudian zeolit NaY disintesis menggunakan material hasil pretreatment menggunakan teknik seeding dan metode hidrotermal dengan rasio molar dan variasi waktu kristalisasi satu hari dan dua hari. Berdasarkan pola XRD diperoleh zeolit NaY berbasis bahan alam yang menunjukkan puncak khas zeolit NaY pada 2θ = 6,3o ; 15,6o ; dan 24,9o dengan rasio Si/Al sebesar 4,1. Kemudian zeolit NaY berbasis bahan alam dimodifikasi menjadi bentuk H+ menggunakan metode pertukaran kation untuk memperbanyak situs asam dan meningkatkan kemampuan katalitiknya sebagai katalis perengkahan n-heksadekana. Zeolit HY hasil modifikasi zeolit NaY kemudian diaplikasikan sebagai katalis perengkahan n-heksadekana. Dengan hasil konversi, yield, dan selektivitas produk gasolin berturut-turut sebesar 59,80%, 59,80%, dan 98,53%. Berdasarkan hasil ini, dapat disimpulkan bahwa zeolit HY berbasis mineral alam memiliki kemampuan selektivitas yang hampir serupa dan dapat dibandingkan dengan zeolit HY sintetik.

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NaY zeolite based on natural minerals was successfully synthesized from Klaten Bayat natural zeolite and Bangka kaolin as a source of alumina and silica. NaY zeolite is synthesized after its synthesis material: Klaten's natural Baye zeolite and Bangka kaolin are pretreated with treatment: activation, purification, fragmentation for Bayat natural zeolite, and silica extraction from Bangka kaolin. Then NaY zeolite was synthesized using pretreatment material using seeding technique and hydrothermal method with molar ratio and variation of crystallization time of one day and two days. Based on the XRD pattern obtained by natural NaY zeolite which shows the typical peak of NaY zeolite at 2θ = 6.3o; 15.6o; and 24.9 o with a Si / Al ratio of 4.1. Then zeolite NaY based on natural ingredients was modified to form H + using cation exchange method to increase the acidic site and increase its catalytic ability as a catalyst for n-hexadecane cracking. Zeolite HY modified from zYolite NaY was then applied as a catalyst for n-hexadecane cracking. With the results of conversion, yield, and selectivity of gasoline products respectively 59.80%, 59.80%, and 98.53%. Based on these results, it can be concluded that natural mineral-based HY zeolites have almost similar selectivity and can be compared with synthetic HY zeolites."

"Parameter proses dalam sirkuit flotasi terus dimodifikasi agar bisa diketahui titik optimal operasi. Evaluasi penggunaan titik penambahan SIBX dan konsumsi energi dalam mesin flotasi merupakan suatu upaya optimalisasi untuk meningkatkan recovery dalam suatu proses separasi. Penelitian ini diharapkan mampu untuk dapat memaksimalkan kegunaan peralatan dalam mesin flotasi sekaligus dengan mencari efek titik penambahan SIBX dan kecepatan impeller terhadap recovery tembaga dan emas.Dalam percobaannya, penulis menggunakan lima tipe kecepatan impeller dan empat titik penambahan SIBX. Dari variasi percobaan tersebut, harus dilakukan 20 test kinetika flotasi yang dilakukan selama 8 menit dan akan menghasilkan 4 konsentrat dan tailing, lalu dicari berat dan kandungan masing-masingnya. Sehingga bisa didapat grafik hubungan recovery dan waktu.Kecenderungannya dengan tiap variasi kecepatan impeller, SIBX yang menghasilkan kecepatan recovery yang terbaik baik pada tembaga maupun emas yaitu pada 0 min, 2 min, 4 min dan yang terburuk 6 min. Kecepatan recovery tembaga hanya dipengaruhi oleh sifat dan jumlah partikel hidrofobik. Sedangkan pada emas, kecepatan impeller juga membawa pengaruh. Nilai recovery akhir tembaga pada tiap percobaan menunjukkan nilai yang sama yaitu rata-rata sekitar 94%. Nilai recovery akhir emas pada tiap percobaan variasi titik penambahan SIBX menunjukkan nilai yang beragam pada tiap kecepatan impeller.

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Process parameters in the flotation circuit continues to be modified in order to know the optimal operating point. Evaluation of the use of SIBX addition point and energy consumption in the flotation machine optimization is an attempt to improve recovery in the separation process. This research is expected to be able to maximize the use of the equipment in the flotation machines and finding the effect of SIBX addition point and the impeller speed towards the recovery of copper and gold.

In the experiments, the authors vary the impeller speed and the SIBX addition points. The impeller speed is varied into five different speed. While the SIBX addition point into four different point. From the variation of the experiment, the test must be done within 20 flotation kinetics. Those test were performed for 8 minutes and will generate 4 concentrates and tailings, and then measure the weight and content of each. So that, the graphs which defines the relationship between recovery and time can be attained.

Of all the speed variations used in the impeller, the best kinetic recovery comes from the addition of SBX in the 0 min, 2 min and 4 min. While the worst comes from the addition in the 6 min. Copper kinetic recovery is only affected by the nature and amount of hydrophobic particles. While in gold, the result is also affected by impeller speed. Copper recovery at each end of the experiment showed the same value that is an average of about 94%. On the other side, the gold recovery shows the dependency upon the impeller speed."

"Daerah prospek Anjing Hitam merupakan daerah prospek endapan mineral yang berada di Kabupaten Dairi, Provinsi Sumatra Utara. Pada daerah prospek ini terdapat endapan bijih tipe Sedimentary Exhalative (SEDEX) dengan kandungan Zn-Pb-Ag dengan keberadaan tubuh bijih sebagian besar terdapat pada Formasi Kluet yang merupakan bagian dari Grup Tapanuli. Daerah prospek Anjing Hitam berada pada wilayah konsesi tambang PT Dairi Prima Mineral dan sudah dilakukan eksplorasi dan eksploitasi. Pada tahun 2020 ditemukan adanya indikasi keterdapatan endapan bijih tipe SEDEX pada Formasi Alas yang berlokasi di Kecamatan Tanahpinem dan sekitarnya, Kabupaten Dairi. Penelitian ini bertujuan untuk mengidentifikasi dan menentukan karakteristik mineral bijih pada sampel yang diambil dari lokasi penemuan endapan bijih tipe SEDEX tersebut. Metode yang digunakan pada penelitian ini yaitu analisis makroskopis, petrografi, mineragrafi dan XRF (X-ray Fluorescence). Hasil analisis menunjukkan karakteristik endapan SEDEX Formasi Alas di daerah penelitian secara litologi terdiri dari batulanau, batupasir, batusedimen gamping dan batugamping kristalin. Bijih teramati terbentuk secara syngenetic berupa batulanau dengan tekstur banded dengan mineral bijih berupa mineral sulfida halus berupa slaferit, pirit, kalkopirit dan galena dengan keberadaan mineral sulfat berupa barit. Terdapat alterasi sericitic yang berasosiasi dengan mineralisasi berupa mineral sulfida terdiseminasi dan juga terdapat pengayaan unsur Mn pada endapan SEDEX Formasi Alas di daerah penelitian. Terdapat indikasi keterjadian supergene yang membentuk gossan pada endapan SEDEX Formasi Alas di daerah penelitian yang ditandai dengan keberadaan batulanau yang teroksidasi derajat tinggi dengan asosiasi mineral berupa hematit, goetit dan kaolinit. Endapan SEDEX Formasi Alas di daerah penelitian mengandung unsur bijih Zn Pb dan Ag. Terdapat pengayaan unsur asosiasi endapan SEDEX berupa Fe, P, Ba, As, Sn, Ga, Ni dan Sb. Berdasarkan karakteristiknya, endapan SEDEX Formasi Alas di daerah penelitian memiliki analogi yang serupa dengan endapan SEDEX pada daerah prospek Anjing Hitam dan endapan SEDEX secara garis besar yang dipublikasikan oleh USGS. Berdasarkan hasil analogi dengan model endapan SEDEX ideal, endapan SEDEX Formasi Alas di daerah penelitian memiliki karakteristik yang sesuai dengan tubuh bijih bagian distal.

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The Anjing Hitam Prospect Area is a prospec mineral deposit area located in Dairi District, North Sumatra Province. This prospect area contains Sedimentary Exhalative (SEDEX) ore deposits containing Zn-Pb with the presence of the ore body mostly in the Kluet Formation which is part of the Tapanuli Group. The Anjing Hitam prospect area is in the mining concession area of ​​PT Dairi Prima Mineral which has already been explored and exploited. In 2020, there is an indication that the presence of SEDEX-type ore deposits was found in the Alas Formation located in Tanahpinem District and its surroundings, Dairi Regency. This study aims to identify and determine the characteristics of ore minerals in samples taken from the location of the discovery of the SEDEX type ore deposit. The methods used in this research are macroscopic analysis, petrography, mineragraphy and XRF (X-ray Fluorescence). The results of the analysis show that the characteristics of the Alas Formation SEDEX deposits in the study area are lithologically composed of siltstone, sandstone, limestone sedimentary rock and crystalline limestone. The ore was observed to be syngenetically formed in the form of siltstone with a banded texture with ore minerals in the form of fine sulphide minerals such as slaferrite, pyrite, chalcopyrite and galena with the presence of sulfate minerals in the form of barite. There is sericitic alteration associated with mineralization in the form of disseminated sulfide minerals and there is also an enrichment of Mn in the SEDEX deposit of the Alas Formation in the study area. There are indications of the occurrence of a gossan-forming supergene in the SEDEX deposit of the Alas Formation in the study area which is characterized by the presence of highly oxidized siltstone with mineral associations such as hematite, goethite and kaolinite. The Alas Formation SEDEX deposit in the study area contains elements of Zn, Pb and Ag ores. There is enrichment of association elements of SEDEX deposit in the form of Fe, P, Ba, As, Sn, Ga, Ni and Sb. Based on its characteristics, the Alas Formation SEDEX deposit in the study area has a similar analogy to the SEDEX deposit in the Anjing Hitam prospect area and the general SEDEX deposit published by the USGS. Based on the results of an analogy with the ideal SEDEX deposit model, the Alas Formation SEDEX deposit in the study area has characteristics that match the distal ore body."

"The Pongkor fold-silver epithermal deposit is located 80 km at South-west of Jakarta, Indonesia, contains more than 98 tons of gold and 1030 tons of silver, with average grades of 18.7 g/t Au and 188.3 g/t Ag. It consists of four main steeply dipping quartz veins located close to the internal border of a Miocene volcano tectonic depression due to an explosive ignimbritic eruption. Mineralized bodies are thick, usually banded, quartz-carbonate-adularia veins due to tectonic extension. GSQ facies is the sulfide-richest and related to the highest gold and silver grades of the veins. Sulfides are dominated by pyrite, with common acanthite-aguilarite and polybasite-pearceite. Electrum is common also, with gold values ranging from 48-74 wt% Au. Sphalerite, galena, chalcopyrite and hessite are fairly uncommon, moreover present within the CQ facies. A strong weathering has affected the ore deposit, down to 250 m below the surface. This supergene action is thus responsible for appearance of manganese oxides layers gold enrichment."

"Peristiwa tanah longsor disebabkan oleh beberapa faktor seperti aktivitas manusia, pengaruhgeologi dan morfologi, namun salah satu mekanisme pemicu pada longsor adalah kandunganlempung dalam tanah. Penelitian ini bertujuan untuk menganalisis komposisi dan distribusimineral lempung yang terdapat pada lokasi-lokasi terjadinya peristiwa tanah longsortersebut. Metode yang digunakan dalam penelitian ini adalah: 1) pengambilan data lapanganmenggunakan disturb soil sampling; dan 2) analisis laboratorium XRD untuk mengetahuikomposisi dan distribusi mineral lempung. Dengan menganalisis hubungan tersebut, hasil penelitian ini berpotensi dijadikan parameter upaya pencegahan tanah longsor, pada lokasi lainnya dengan karakteristik yang sama. Harapannya, penelitian ini dapat membantu upaya pencegahan tanah longsor terutama bagi masyarakat di daerah rawan longsor.

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Landslide events are caused by several factors such as human activities, geological and morphological influences, but one of the triggering mechanisms for landslides is the clay content in the soil. This study aims to analyze the composition and distribution of clay minerals found at the locations of the landslide events. The methods used in this research are: 1) field data collection using disturb soil sampling; and 2) XRD laboratory analysis to

determine the composition and distribution of clay minerals. By analyzing this relationship, the results of this study have the potential to be used as parameters for landslide prevention efforts, in other locations with the same characteristics. It is hoped that this research can help prevent landslides, especially for people in landslide-prone areas."

"This book is a collection of papers that are devoted to various aspects of interactions between mineralogy and material sciences. It will include reviews, perspective papers and original research papers on mineral nanostructures, biomineralization, micro- and nanoporous mineral phases as functional materials, physical and optical properties of minerals, etc. "