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14 SMT Magazine • October 2017 ification by 3.32%. Overall, bismuth's versatile properties make it an intriguing element to design alloys. Table 1 summarizes the properties of bis- muth. Natural Resources The level of natural resources of bismuth is about the same as Ag. Elemental bismuth may occur naturally, although its sulfide and oxide form important commercial ores. It is found most in Australia, Bolivia, Can- ada, China, Japan, Korea, Peru, Mexico, and USA. However, Bolivia, Australia and China are the only lands where native Bi is available. Due to its lack of wide presence in the native state, bismuth is usually associated with copper, lead, tin, tungsten, silver and gold ores. Yet in China, a major proportion is associated with tungsten. Bismuth has always been produced mainly as a byproduct, and its price historically reflect- ed the cost of recovery and the balance between production and demand. The world mine production in 2016 stands at approximately 10,000–11,000 metric tons, with major contributions from China, Vietnam and Mexico, and the world reserves at 370,000 met- ric tons (Source: USGS). The United States ceased production of primary refined bismuth in 1997 and is highly import-dependent for its supply. Bi Safety Data Bismuth is widely recognized by the scien- tific community as one of the safest el- ements available. In practical terms, it has been regarded as non-toxic. Its only regulated uses are in pharmaceu- tical and cosmetic applications. It was approved by US EPA/NSF for substitu- tion of Pb in free-cutting brasses for drinking water fittings in the U.S. A number of literatures cover the studies of Bi and Bi-compound safety. Table 2 lists the relative rank of toxicity per U.S. OSHA – PEL. Application Areas Bi-compounds have been used for burn bandage dressings, antisep- tic powders, and the treatment of ve- nereal diseases. As reported, other pharma- ceutical areas engaging Bi-compounds include its use as a pre-treatment to reduce the lethal toxicity of several forms of cancer therapy and the use as an additive to special polymers for bone implants. In addition, Bi-Ge oxide cr ystals have their place in diagnostic devices by its virtue of neutralizing lethal gamma rays and improving overall imaging quality. In the chemical world, Bi catalysts are wide- ly used in industrial organic chemistry, and Bi- compounds are popular pigments for health and beauty care. Toys and industrial applica- tions that require non-toxic yellow to red or green pigments also rely on Bi compounds. For example, bismuth oxychloride pigment's bril- liance and luster is an effective ingredient to generate the pearlescent effect in lipsticks, nail polishes and make-up powders. Another com- pound, Bi citrate, is found to contribute to im- THE ROLE OF BISMUTH (BI) IN ELECTRONICS, PART 1 Table 1: Physical properties of bismuth (Bi). Table 2.