Michael Harding Dammar Glaze Medium 250ml will add depth & gloss to transparent oil colours & also speed drying. Michael Harding mediums are unique formulations based on ingredients dating back to the 13th century, using natural materials such as resins, waxes & balsams. This contains cobalt as a siccative (drying agent), as well as Indonesian dammar resin with double rectified turpentine which evaporates more slowly than the usual mastic resin. Adding just 10-20% Michael Harding Dammar Glaze Medium will speed the drying of oil paints, while you can also add this in a proportion of 1:1 to any other Michael Harding medium. UK shipping by road only. Not available for International or Northern Ireland delivery.