With America’s 250th birthday approaching on July 4, it can seem like George Washington is everywhere, from a live PBS broadcast with Ken Burns at Colonial Williamsburg to two-part screenings of the musical. hamilton where actor Christopher Jackson plays the Revolutionary War hero.

But at Morristown National Historical Park in New Jersey, visitors can almost touch the first president of the United States, or at least part of his jacket. In honor of the country’s semi-quincentennial, the park commemorating the encampment of the Continental Army from December 1779 to June 1780 has put together a special exhibit showcasing elements of early American history. George Washington’s coat is included, but this is no ordinary suit jacket. It is the coat that George Washington wore to his inauguration night ball in 1789.

Originally known as his “gold suit” because of its brilliant golden yellow color, careful analysis of the garment by the Smithsonian and Morristown National Historical Park revealed that it was not gold at all.

Dr. Asher Newsome, a physical chemist at the Smithsonian Museum Conservation Institute, used a special technique known as mass spectrometry to analyze a small number of fur fibers.

Don’t worry, the Founding Father’s valuable suit was not touched. The fibers Newsome analyzed had just fallen out of the coat thanks to Father Time. Curators often refer to these types of specimens as “self-sampled.”

Once Newsome received these self-sampled fibers in the mail from Morristown, he got to work. Using a technique called Direct Analysis in Real-Time Mass Spectrometry (or DART-MS), Newsome was able to discover the exact natural dyes used in the famous coat.

“Today, there are thousands of synthetic dyes, but there are a very small number, relatively, of natural dyes,” Newsome says. Popular science.

After performing a DART-MS analysis, Newsome was able to observe the chemical signatures present in the fibers. He then compared those signatures to the known chemical signatures of different natural dyes to determine exactly which dyes were present in the Washington lawsuit.

And Newsome didn’t just find one dye: he found a variety of different natural dyes from around the colonial world. “There’s shellac, which comes from an insect. There’s madder,” he says, “which comes from a root. There’s Brazil wood, walnut, and logwood. These are all dyes that have been positively identified.”

Each of these dyes creates a range of different colors. Shellac, which comes from an insect. Kerria lacca Native to India and Southeast Asia, it creates a color between crimson and deep purple. Madder comes from the roots of flowering shrubs of the genus. rubiaceaeand creates a strong red color. Like shellac, Brazil wood can create a red or purple color. Walnut creates browns and tans. And finally, logwood produces a rich royal purple color.

Based on Newsome’s analysis, curators at Morristown National Historical Park created a replica of Washington’s suit using the exact natural dyes present in the original. The replica was not a golden color at all, but a rich and vibrant plum color.

In fact, when a piece of plum-dyed silk was left in the sun, it turned a golden yellow color. That might explain how Washington’s famous coat turned gold in the centuries since he celebrated his inauguration.

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