While comparing Chrome-Chalcedony and Onyx 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 Chrome-Chalcedony and Onyx chemical formula.
Another important criteria for qualitative analysis of gemstones is Chrome-Chalcedony and Onyx Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Chrome-Chalcedony and Onyx Optical Properties during the identification of gemstone. Specific gravity of Chrome-Chalcedony is 2.55-2.70 whereas that of Onyx is 2.55-2.70.