Best wishes for a fun filled summer day on this 4th of July to all! Many of you will be enjoying a fireworks display this evening but have you ever wondered what makes all those brilliant colors? Well, according to the USGS it comes from the minerals that are used… here’s some details:
Red Fireworks and Strontium—Strontium gives a brilliant red hue to fireworks and to the flares you might be toting in your car in case of roadside emergencies. Strontium is produced most notably in the mineral celestite. Strontium is used in drilling fluids to produce oil and gas; it also strengthens metal castings in airplanes and cars, and makes paints that resist corrosion.
Blue Fireworks and Copper — Copper turns fireworks a dazzling blue. Copper occurs naturally in the Earth’s crust in a variety of forms, most commonly it is found with sulfur as the mineral chalcopyrite. Azurite and malachite are common copper minerals known for their blue and green colors. Copper can also be found as pure “native” copper.
Green Fireworks and Barium—Barium nitrate and chlorate produce bright green fireworks.
Barium is a metallic element that is not found in nature in its native form. It occurs principally as the mineral barite (barium sulfate), and its dominant use is in oil well drilling fluids. Barite is also used in making paints, plastic, and rubber. Your car’s brakes, paint primer, and rubber mudflaps might contain barite. Ultrapure barite is used as a contrast medium in medical x-rays.
Golden Sparks and Iron—Iron filings produce the golden sparks that shower out of a main fireworks explosion. Iron is one of the most abundant elements on Earth, but it does not occur naturally in the Earth’s crust in native form (Fe). It is found only in ores, principally hematite (Fe2O3) and magnetite (Fe3O4). By definition, steel is iron with a small amount of carbon
Bright Flashes and Aluminum—Bright flashes and loud bangs in fireworks come from aluminum powder. Aluminum is the second most abundant metallic element in the Earth’s crust after silicon, yet it is a comparatively new industrial metal that has been produced in commercial quantities for just over 100 years.
More details here on the USGS and see also The USGS Mineral Resources Program