Boron oxide polymorphism

By itself not particularly strong or durable, aluminum in combination with other metals becomes one of the most versatile materials available. It does take vast amounts of electrical energy to manufacture, however, and presently this involves the production of both carbon dioxide and the sulfur oxides. Alums are astringents and the sources of beautiful crystals. Alumina, the oxide, comes in a variety of polymorphs used as various abrasives and in beautiful, gem-quality minerals. It is also the product of the extremely exothermic thermite reaction. Boron Neutron Capture Therapy (BNCT) offers a potential treatment against brain tumors and other difficult-to-treat carcinomas of the head and neck. Gallium, indium, and thallium compounds do not have many applications. 

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