Barium ferrite these species include BaFeO, BaFeO, and BaFeO. A one-step hydrothermal process can be used to form crystals of barium ferrite, by mixing barium chloride, ferrous chloride, potassium nitrate, and sodium hydroxide with a hydroxide to chloride concentration ratio of 2:1. Nanoparticles are prepared from ferric nitrate, barium chloride, sodium citrate, and sodium hydroxide. The typical preparation, however, is by calcining barium carbonate with iron(III) oxide: Barium ferrite has been considered for long term data storage. The material has proven to be resistant to a number of different environmental stresses, including humidity and corrosion. Because ferrites are already oxidized it can
Sterling silver products. Colonial silversmiths used many of the techniques developed by those in Europe. Casting was frequently the first step in manufacturing silver pieces, as silver workers would melt down sterling silver into easily manageable ingots. Occasionally, they would create small components (e.g. teapot legs) by casting silver into iron or graphite molds, but it was rare for an entire piece to be fabricated via casting. Next, silversmiths would forge the ingots into the shapes they desired, often hammering the thinned silver against specially shaped dies to "mass produce" simple shapes like the oval end of a spoon. This process occurred