It's rare to see portraits of any of the Founder generation as teenagers. In the 18th century, very few people ever had their portraits painted, and then only after they'd become older, famous, and rich.
He is certainly dressed for it, in costly silk and lace and a black silk bow at his throat. His cocked hat is tucked beneath his arm, as a gentleman does, and his hand rests lightly on the hilt of his dress sword. The ornamental loop on his shoulder may refer to his rank as second lieutenant in the King's Musketeers.
His side curls called buckles are pinned neatly into place, and his queue ponytail is clubbed and beribboned. Then his entire head was dusted with white powder - the height of formality for court. When this portrait was painted, he was in most ways already regarded as an adult. Intheir first daughter - Henriette du Motier - was born.
He was wounded in the leg, but heroically continued to command as long as he could. about Eliza and Alexander Hamilton in my latest historical novel, I, Eliza Hamiltonnow available everywhere.