Etude Rosin$10.00 Etude Rosin for violin, viola and cello. Made by the Gustave Bernadel company. Etude Rosin quantity Add to cart Description Description Etude is a medium priced transparent amber rosin mounted on a light suede-look cloth. Suitable for violin, viola and cello. For more on the various different rosins available, see our news item on Rosins.