While comparing Scorodite and Gahnite physical properties, the important data you should know is its chemical composition. Since chemical formula defines the molecular structure of the crystal, most of the physical properties like color, tenacity, solubility are governed by Scorodite and Gahnite chemical formula.
Another important criteria for qualitative analysis of gemstones is Scorodite and Gahnite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Scorodite and Gahnite Optical Properties during the identification of gemstone. Specific gravity of Scorodite is 4.00-4.62 whereas that of Gahnite is 4.00-4.62.