Emery is an impure fine-grained form of corundum (aluminiumoxide) of blackish or bluish-grey colour, chiefly found in shapeless masses and mixed with other minerals.in conjunction with iron oxides and spinel. Emery is very hard; is infusible, and is not attacked by acids; has the formulae Al2O3 employed widely as an abrasive: it is employed in cutting and polishing precious stones; in smoothing the surface of the finer kinds of lenses preparatory to their being polished; in the polishing of marble; by cutlers, locksmiths, glaziers, and other artisans. For all these purposes it is pulverized in large iron mortars or in steelmills, and the powder, which is rough and sharp, is carefully washed and sifted into eight or ten different degrees of fineness. Emery-paper and emery-cloth are made by laying a thin coat of glue upon the fabric, and dusting the emery from a sieve of the required size. Typically emery consists of 60 percent corundum and 40 percent iron oxide in the form of magnetite. Research Emery
Ironstone is a rock containing at least fifteen percent iron. Ironstone forms in igneous rocks through mahmatic differentiation - dense heavy minerals such as magnetite crystallise first and sink to the base of the molten magma to form an iron-rich layer. Ironstone also forms in sedimentary rocks such as limestone and sandstone. Research Ironstone
Lepidocrocite is a secondary mineral that is generally found in association with goethite and other iron-bearing minerals, especially hematite, ilmenite, limonite, magnetite, pyrite and siderite. Lepidocrocite is very similar to goethite, the two having the same chemical formula but differing in specific gravity - due to the different manner in which they formed - lepidocrocite being heavier. Research Lepidocrocite
Magnetite is an oxide of iron occurring in isometric crystals, also massive, of a black colour and metallic lustre. It is readily attracted by a magnet and sometimes possesses polarity, being then called loadstone. It is an important iron ore and is also called magnetic iron. Magnetite has the formulae Fe3O4 and a relative hardness of 7. Research Magnetite
The people's Republic of China is a country in east Asia. It is divided into provinces and has a total area of 9,596,960 km2. The climate is extremely diverse; tropical in the south to sub-arctic in north. The terrain is mostly mountains, high plateaus, deserts in west; plains, deltas, and hills in the east. Natural resources are coal, iron ore, crude oil, mercury, tin, tungsten, antimony, manganese, molybdenum, vanadium, magnetite, aluminium, lead, zinc and uranium, China also has the world's largest hydropower potential. The religion is officially atheist, but traditionally pragmatic and eclectic; most important elements of religion are Confucianism, Taoism, and Buddhism (introduced around 65 AD); about 2-3% Muslim, 1% Christian. The language is Standard Chinese (Putonghua) or Mandarin (based on the Beijingdialect); also Yue (Cantonese), Wu (Shanghainese), Minbei (Fuzhou), Minnan (Hokkien-Taiwanese), Xiang, Gan, Hakka dialects, and other Chinese languages are also spoken, in all there are 201 currently used Chinese languages and one extinct Chinese language.
China was at one time known by its Tartar name of Cathay, meaning 'Middle Kingdom'. In 1900, the Chinese empire was the third largest in the world, just smaller than those of Britain and Russia.
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Research Emery
