The metabidiminished icosahedron is a convex equilateral solid that is Johnson solid .
The unit metabidiminished icosahedron has volume
and Dehn invariant
where the first expression uses the basis of Conway et al. (1999). It can be dissected into the pentagonal antiprism (E. Weisstein, Sep. 6, 2023).
More things to try:
Weisstein, Eric W. "Metabidiminished Icosahedron." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/MetabidiminishedIcosahedron.html