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About Magnesite
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Contents
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Natural Status of Magnesite
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Commodity Category |
Nonmetal minerals
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Crystal Structure and Habit |
Trigonal crystal system, shows itself in rhombohedron, often presents dense granular aggregate. |
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Chemical Composition and Property |
Essential constituent is magnesium carbonate（MgCO3）, among which MgO takes up 47.81％，CO2
takes 52.19％ in the chemical constitution. There are often some impurities of oxide compounds such as those of iron, manganese, calcium, silicon etc.
Magnesite shrinks and CO2 is decomposed out when heated to about 640°C; it becomes caustic calcined magnesite of loosening lumps of light yellow or white color when heated to 700-1,000°C, which is of very strong adhesivity;
it is completely decomposed when heated to 1,400-1,800°C and forms periclase, becoming dead burned magnesite of dark brown color that is of very high refractoriness; it becomes fused magnesite
of white or light brown color when melted to 2,500-3,000°C in electric arc furnace, which is of much higher refractoriness and electrical insulating property.
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Physical Property |
It is of white or light yellow-white or off-white color, sometimes bearing red tone while ceramic magnesite of snow-white color; some variants feel sticky; with glass glance; hardness is 4-4.5; friable; specific gravity is 2.9-3.1, bigger when containing iron; showing achromatic color under
microscope transmitting light; of very high refractoriness and binding property. |
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Category |
1.Macrocrystalline (coarse crystalline) natural magnesite: belonging to rich-iron and less-rich-in-iron magnesite, produce mainly in China, North Korea, Russia, Czech, Brazil, Spain, and Australia.
2.Cryptocrystalline natural magnesite: belonging to low-iron magnesite, produce mainly in Greece, Turkey, Yugoslavia but resources are on the verge of exhaustion.
The magnesite being produced in Liaoning, China is less-rich-in-iron macrocrystalline natural magnesite featured by enormous deposit, high grade of tenor (MgO≥46% takes up 40%), low cost of exploitation.
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Main Applications |
Magnesite is one of feed minerals for making magnesium as well as refractory for manufacturing refractory bricks, linings of steel-making furnace and the like. Besides, it is widely used in building, chemical, rubber and other industrial fields such as for making magnesite cement, for buildings of heat
preservation, heat shielding, sound insulating, and so on. In chemical industry, as mordant, desiccant, dissolution agent, decolorizing agent, neutralizing agent, absorbent. In addition, it is also widely used in the manufacture of artificial fiber, fertilizer, plastic, and cosmetic. |
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Classification and Definition for Magnesia, Magnesite Goods, Magnesite Finished Products and Magnesite-based Chemicals* |
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Magnesia |
Dead burned magnesite and fused magnesite through processes of sintering or melting of magnesite, dolomite or magnesium oxide extracted from serpentine, brucite, sea water, or brine are so called as magnesia. Nowadays in China, magnesia is produced directly from natural magnesite with very low
cost while in some other countries it is made from sea water or brine with higher purity but also higher cost. |
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Magnesite Goods and its Commodity Name, HS Code |
Magnesite - 25191000, Caustic calcined magnesite - 25199010, Dead
burned magnesite - 25199020, Fused magnesite - 25199030, Gunning
material - 25199020, only corresponding to those of MgO≥70%).
Above commodities are now generally designated as magnesite goods and among the lists of commodities of export license control in China.
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Magnesite Finished Products |
Finished products processed from above mentioned magnesite goods and mainly used in refractory field such as various magnesia-based bricks, caustic calcined magnesite ball/briquette and gunning materials etc. that contain MgO<70%. |
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Magnesite-based Chemicals |
Those chemically made of magnesite such as magnesium oxide, lightweight magnesium oxide, magnesium sulphate, magnesium carbonate, and magnesium fertilizer. |
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Status of Production and Consumption of Magnesite Goods** |
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World Status of Production and Consumption |
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Reserves and Geographic Distribution |
There are about 3.5 billion tons of natural magnesite reserve in the world mainly distributed in China, Russia, North Korea, Brazil, Australia, Turkey, Greece, India, and USA. |
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Output and Distribution |
The world's annual output including calcined magnesite, dead burned magnesite and fused magnesite is about 7 million tons, mainly from countries of China, North Korea, Turkey, India, Russia, Australia, Greece, Spain, Yugoslavia, Czech, Brazil, Austria etc. |
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Main Consuming Country or Region |
USA, Europe, Japan, Korea, Southeast Asia, China, Taiwan
of China, etc. |
* The category and definition only represent opinions of this site.
** The
data are cited from the CCCMC relevant
information, some of which were modified by this site.
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