alpha – Iron
Iron makes up 5 percent of the Earth’s crust and is second in abundance to aluminum among the metals and fourth in abundance behind oxygen, silicon, and aluminum among the elements. Iron, which is the chief constituent of the Earth’s core, is the most abundant element in the Earth as a whole (about 35 percent) and is relatively plentiful in the Sun and other stars. In the crust the free metal is rare, occurring as terrestrial iron (alloyed with 2–3 percent nickel) in basalistic rocks in Greenland and carbonaceous sediments in the United States (Missouri) and as a low-nickel meteoric iron (5–7 percent nickel), kamacite. Nickel-iron, a native alloy, occurs in terrestrial deposits (21–64 percent iron, 77–34 percent nickel) and in meteorites as taenite (62–75 percent iron, 37–24 percent nickel). (For mineralogical properties of native iron and nickel-iron, see native elements [table].) Meteorites are classified as iron, iron-stone, or stony according to the relative proportion of their iron and silicate-mineral content. Iron is also found combined with other elements in hundreds of minerals; of greatest importance as iron ore are hematite (ferric oxide, Fe2O3), magnetite (triiron tetroxide, Fe3O4), limonite (hydrated ferric oxide hydroxide, FeO(OH)∙nH2O), and siderite (ferrous carbonate, FeCO3). Igneous rocks average about 5 percent iron content. The metal is extracted by smelting with carbon (coke) and limestone.
This model is hand made in the USA by Klinger Educational Products. This is a permanent structure. We only use grade A materials. The 1 inch balls are made of hard Maplewood that includes an enameled painted finish. Polished steel rods are used to connect the wooden balls together.
alpha-Iron Contains 9 – 1 inch balls.