While comparing Diopside and Titanite 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 Diopside and Titanite chemical formula.
Another important criteria for qualitative analysis of gemstones is Diopside and Titanite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Diopside and Titanite Optical Properties during the identification of gemstone. Specific gravity of Diopside is 3.48-3.60 whereas that of Titanite is 3.48-3.60.