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AMERICA'S GLOBAL DEPENDENCY FOR NEARLY EVERYTHING
Sunday, July 4, 2010
Strontium carbonate (red) and barium chloride (green) tint modern skyrockets and other fireworks. Lighter red may come from lithium carbonate with orange provided by calcium chloride. Blues usually indicate the presence of copper compounds, which also produce purple when mixed with strontium. Rarely, rubidium generates purple. Sodium makes yellow, iron makes gold. Burning titanium, aluminum, or magnesium metal powder is the basis for intense white or silver stars. Strontium also makes red color in highway flares.
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Photo in public domain, via Wikipedia