Zircon is a well-known mineral that makes an important gemstone of of many colors. Its brilliant luster and fire, combined with good hardness, make it a desirable gem.
Natural Zircon with good color and transparency is uncommon; most Zircon crystals are opaque and brownish. However, most Zircon gemstones, especially the blue and white forms, are enhanced by heat treatment.
Niobium and columbium are synonymous names for the chemical element with atomic number 41; columbium was the name given in 1801, and niobium (Nb) was the name officially designated by the International Union of Pure and Applied Chemistry in 1950.
Niobium in the form of ferroniobium is used worldwide, mostly as an alloying element in steels and in superalloys. Appreciable amounts of niobium in the form of high-purity ferroniobium and nickel niobium are used in nickel-, cobalt-, and iron-base superalloys for such applications as jet engine components, rocket subassemblies, and heat-resisting and combustion equipment.
Tantalum is a refractory metal with unique electrical, chemical, and physical properties that is used mostly as tantalum metal powder in the production of electronic components, mainly tantalum capacitors. Alloyed with other metals, tantalum is also used in making cemented carbide tools for metal working equipment, and in the production of superalloys for jet engine components
Vanadium, when present in small amounts in certain ferrous alloys, can significantly improve their properties. Manufacturers of automobiles and machinery recognized the toughness and fatigue resistance of vanadium alloys as far back as the early 1900's, incorporating the alloys in axles, crankshafts, gears, and other critical components. Vanadium has been used together with aluminum to give the required strength in titanium alloys used in jet engines and high-speed airframes.