TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The method comprises: (a) carbon-coating precursors, where coating comprises (i) providing a first compound comprising a metal, (ii) providing a second compound comprising boron and (iii) decomposing a hydrocarbon gas in the presence of the first compound and the second compound; and (b) reacting the carbon coated first compound and the carbon coated second compound at a predetermined temperature for a predetermined time sufficient to form a metal boride. The step of providing the first compound comprises decomposing a hydrocarbon gas in the presence of a compound comprising the metal. The step of providing the second compound comprises decomposing a hydrocarbon gas in the presence of a compound comprising boron. The step of carbon-coating the first or second compound: occurs at a pressure of 15-50 pounds per square inch (psi), a temperature of 100-1000 degrees C and in an inert atmosphere; and comprises 10-30 cycles of a carbon coating reaction. The one cycle of carbon coating the first compound or the second compound comprises 10-30 minutes. The reacting the first compound and the second compound occurs: at a temperature of at least 1000 degrees C; at a temperature increase or decrease rate of 1 degrees C per minute or 10 degrees C per minute; in an inert atmosphere; and for 1-6 hours. The metal boride comprises an average particle size of diameter 100-1000 nm. The metal boride comprises an average specific surface area of 0.1-10 m2 g-1. Preferred Components: The first compound is a carbon coated first compound, or the second compound is a carbon coated second compound. The first compound comprises a metal including calcium, calcium oxide, calcium hexaboride, calcium carbonate, aluminum hydroxide, neodymium yttrium aluminum borate, aluminum oxide, aluminum borohydride, an aluminum salt, zirconium dioxide and/or aluminum oxide. The boron comprises boron carbide, diboron trioxide, and/or boric acid. The hydrocarbon gas comprises methane, ethane, propane, butane, propylene, 1,3 butadiene, acetylene, allene, butene, neopentane, ethylene, methylacetylene, and/or natural gas. The reaction of the first compound and the second compound is carried out with 1% of iron or 1% of nickel. EXAMPLE - Calcium carbonate (2 moles), boron carbide (3 moles) and carbon black were taken and mixed together. The mixture was coated with 20 cycles of carbon using propylene cracking at 550 degrees C in the reactor tube. The precursors were then reacted at 1600 degrees C, 1500 degrees C and 1400 degrees C under flowing argon for 4 hours to obtain single phase, chemically pure calcium hexaboride.