Question: Siberian-Urals Aluminium Company comprises 19 businesses involved in the production of a chemical compound that naturally in what crystalline polymorphic phase?

Lead(IV) oxide, commonly called lead dioxide or plumbic oxide or anhydrous plumbic acid (sometimes wrongly called lead peroxide ), is a chemical compound with the formula PbO.  It is an oxide where lead is in an oxidation state of +4.  It is of an intermediate bond type, displaying both ionic (e.g. the lattice structure) and covalent (e.g. its low melting point and insolubility in water) properties.  It is an odorless dark-brown crystalline powder which is nearly insoluble in water.  It exists in two crystalline forms.  The alpha phase has orthorhombic symmetry; it was first synthesized in 1941 and was identified in nature as a rare mineral scrutinyite in 1988.  The more common tetragonal beta phase was first identified as the mineral plattnerite around 1845 and later produced synthetically.  Lead dioxide is a strong oxidizing agent which is used in the manufacture of matches, pyrotechnics, dyes and other chemicals.  It also has several important applications in electrochemistry, in particular in the positive plates of lead acid batteries. <SEP> Siberian-Urals Aluminium Company (Russian: Сибирско-Уральская Алюминиевая Компания ), commonly known as SUAL (Russian: СУАЛ ), is a fully vertically integrated aluminium company that ranks amongst the world's top ten aluminium producers.  It comprises 19 businesses that are located in nine Russian regions and are involved in the production of bauxite, alumina, primary aluminium, silicon, semi-finished and finished aluminium products.  The Group's revenue for the year ended December 31, 2003 was USD 1.7 billion.  It has some 62,000 employees. <SEP> Countercurrent distribution (CCD, also spelled "co "counter current" distribution) is an analytical chemistry technique which was developed by Lyman C. Craig in the 1940s.  Countercurrent distribution is a separation process that is founded on the principles of liquid-liquid extraction where a chemical compound is distributed (partitioned) between two immiscible liquid phases (oil and water for example) according to its relative solubility in the two phases.  The simplest form of liquid-liquid extraction is the partitioning of a mixture of compounds between two immiscible liquid phases in a separatory funnel.  This occurs in five steps: 1) preparation of the separatory funnel with the two phase solvent system, 2) introduction of the compound mixture into the separatory funnel, 3) vigorous shaking of the separatory funnel to mix the two layers and allow for mass transfer of compounds in and out of the phases, 4) The contents of the separatory funnel are allowed to settle back into two distinct phases and 5) the two phases are separated from each other by draining out the bottom phase.  If a compound is insoluble in the lower phase it will distribute into the upper phase and stay in the separatory funnel.  If a compound is insoluble in the upper phase it will distribute into the lower phase and be removed from the separatory funnel.  If the mixture contains one or more compounds that are soluble in the upper phase and one or more compounds that are soluble in the lower phase, then an extraction has occurred.  Often, an individual compound is soluble to a certain extent in both phases and the extraction is, therefore, incomplete.  The relative solubility of a compound in two phases is known as the partition coefficient. <SEP>  It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) oxide.  It is commonly called alumina, and may also be called aloxide, aloxite, or alundum depending on particular forms or applications.  It occurs naturally in its crystalline polymorphic phase α-AlO as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire. Aluminium oxide (British English) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula Al O .  AlO is significant in its use to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point.