Description General description Canada Balsam is a natural mounting medium obtained from balsam fir trees. The optical properties of Canada Balsam are nearly identical with those of glass. Specimens must be dehydrated before using this medium. Permanent slides mounted with Canada Balsam have been stored for over a century. Application Canada balsam has been used as a mounting medium for cellular staining. Packaging 25, 100 mL in glass bottle