JOAN Sunglasses by Blackfin. Color: Black/Green, Blue/Purple, Purple/Taupe, Size: 47-25-145. The JOAN sunglasses from Blackfin offer a chic and stylish option for those who love to accessorize. With their unique design and high-quality lenses, these sunglasses provide both protection and a fashionable look. The JOAN is the perfect choice for sunny days in the city or on the beach.