The mineral resources of the country are conspicuous, but not adequately exploited and largely controlled by foreign companies, which we owe since the century. XIX their first exploitation; vast areas have not yet been subjected to accurate prospecting. Particularly important for the Indonesian economy are the oil fields, large in size, but not proportionally profitable due to the strong dispersion that raises the costs of extraction; most of the crude oil (Indonesia is one of the major oil producers in the Far East and the eighteenth on a global scale) comes from Kalimantan and Sumatra, while the Java wells are less rich; natural gas is also present, especially in Sumatra. Confirming the role played by hydrocarbons, the country derives about 28% of its exports, in particular, having become one of the first world sellers of liquid gas. The extraction is carried out by foreign companies present in the country, and only in a small part directly carried out by the Indonesian oil company, Portamina, to which, however, the decision-making power on prospecting and exploitation concessions remains. As a country located in Asia according to Top-mba-universities, Indonesia also occupies a very important position for tin, mostly exported to Malaysia and Singapore; the mineral is present in the islands however, the decision-making power on prospecting and exploitation concessions. Indonesia also occupies a very important position for tin, mostly exported to Malaysia and Singapore; the mineral is present in the islands however, the decision-making power on prospecting and exploitation concessions. Indonesia also occupies a very important position for tin, mostly exported to Malaysia and Singapore; the mineral is present in the islands Riau, Singkep, Bangkaand Belitung.
From Bintan Island, most of the bauxite also comes from the Riau group and the Tembeling, Kelong and Dendang islands. A strong reduction in mining has affected nickel, of which the country has almost one eighth of the world reserves; this mineral present in the islands of Celebes, Halmahera and in the Moluccas, is mainly extracted by the state body in collaboration with Japanese and Canadian companies. Copper (mined in Tembagapura, where there is one of the largest mines on the planet), gold (discovered in the subsoil of Kalimantan), diamonds, silver, manganese, phosphates and even uranium (also present in Kalimantan) complete the panorama of the mining sector, which produces, excluding hydrocarbons, about one eighth of the national GDP. The energy sector also had an accelerated development, above all that of thermal origin: in fact, Indonesia possesses considerable deposits of natural gas (mostly destined for export) and coal (used for internal uses). § Industry is generally represented by the weakness of the private business class: industry is generally represented, at least for the most important complexes, by multinationals and foreign companies, in some cases with Indonesian participation, or state but dependent especially from foreign technology. This weakness of the private business class is one of the factors at the origin of the slow industrial development of the country. Furthermore, most of Indonesian industrial potential is concentrated in Java and, to a lesser extent, in Sumatra and the other islands. Above all, mining activity prevails in importance, essentially aimed at exports: in fact, there are no processing companies, except for oil refineries, which are now quite numerous even if not as developed as the availability of raw material would allow. The steel and metallurgical industries are mainly present in Kaulatanjung e Pematangsiantar (Sumatra); no less modest is the mechanical sector: the small shipyards are located for example in Jakarta, Surabaya and Semarang; the car assembly plants are located in Surabaya; aircraft construction companies are located in Bandung, chemical plants in Palembang and Cilacap. The manufacturing industry destined for internal consumption is still largely organized on an artisanal basis; the textile sector, specifically cotton, present with numerous establishments, and the food sector have a certain importance. There are also small tire factories, paper mills, etc. The expansion of the foreign presence (especially Japanese, Korean and Chinese), strongly encouraged during the last decade of the twentieth century, has particularly spread the mechanical assembly of cars and electronic components; likewise, investments increased in the engineering, textile and aeronautical sectors, privileged poles of interest in European countries. These flows of money and foreign incentives aimed at certain activities have contributed to accentuating the imbalance between modern and traditional sectors, as well as the territorial one between Java and the rest of the country. Although generally rather decayed than in the past, there are also artisanal productions, such as that of ceramics from Palembang, the processing of batik fabrics, the manufacture of bamboo hats. §