Can rosin go bad?
We recommend changing rosin after approx. six to eight months as it tends to dry out after a while. The ethereal oils, crucial for good rosin, evaporate over time and the rosin’s characteristics change as well. In order for your rosin always being ready to use, rub the surface of new rosin with fine sandpaper before using it for the first time and once every week after that. Use 400 grit sandpaper to slightly sand off the dry surface of the rosin until you can smell the ethereal oils again.