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and 20% yttrium oxide, which he called "Actinophor" and patented in 1887 (March 15, 1887, US patent #359,524). These original mantles gave off a green-tinted light and were not very successful. Welsbach's first company established a factory in Atzgersdorf in 1887, but it failed in 1889. In 1889, Welsbach received his first patent mentioning thorium (March 5, 1889, US patent #399,174). In 1891 he perfected a new mixture of 99% thorium dioxide

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