Ductility
Ductility can be quantified by the fracture strain formula_1, which is the engineering strain at which a test specimen fractures during a uniaxial tensile test. Another commonly used measure is the reduction of area at fracture formula_2. The ductility of steel varies depending on the alloying constituents. Increasing the levels of carbon decreases ductility. Many plastics and amorphous solids, such as Play-Doh, are also malleable.
The most ductile metal is platinum and the most malleable metal is gold.
Unbinilium
The Ubn–Au bond should be the weakest of all bonds between gold and an alkaline earth metal, but should still be stable. This gives extrapolated medium-sized adsorption enthalpies (−Δ"H") of 172 kJ/mol on gold (the radium value should be 237 kJ/mol) and 50 kJ/mol on silver, the smallest of all the alkaline earth metals, that demonstrate that it would be feasible to study the chromatographic adsorption of unbinilium onto surfaces made of noble metals. The Δ"H" and −Δ"H" values are correlated for the alkaline earth metals.