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term these structures “nongeneric” in light of the correlations. The degree of “nongenericity” of the packings is quantitatively characterized by the fraction of local structures composed of particles with less contacts than average. Moreover, we showed that such seemingly “spe- cial” packing configurations are not rare. As the anisotropy of the particles increases, the fraction of rattlers decreases while the minimal orientational order increases. The novel fea- tures arising in MRJ packings of superdisks and superballs result from the unique manner in which rotational symmetry is broken. This makes such packings distinctly different from other known MRJ packings of nonspherical particles, such ellipsoids and ellipses. 

The ability to produce dense random packings using superballs casts new lights on sev- eral industrial processes, such as sintering and ceramic formation, where interest exists in increasing the density of powder particles to be fused. If superball-like particles instead of spherical particles are used, the packing density of a randomly poured and compacted powder could be increased to a value surpassing that of the maximal sphere-packing density. We note that superdisks and superballs can be experimentally mass produced using current lithography techniques. Understanding the statistical thermodynamics of the jamming tran- sition of superdisks and superballs, especially the role of rotational and translational degrees of freedom for different deformation parameters is a subject that merits future investiga- tion. Such studies could may our understanding of the nature of glass transitions, since the preponderance of previous investigations have focused on spherical particles. 

## APPENDIX: EQUATIONS FOR LOCALLY JAMMED FOUR-SUPERDISK CONFIGURATIONs 

In this section, we provide the equations that determine locally jammed four-superdisk configurations composed of a trapped central particle and three fixed contacting neighbors (see Fig. 8). In particular, the boundary of a superdisk with radius R is define by 

which can be also expressed by the parametric equations 

<img src='content_image/374630.jpg'>

<img src='content_image/374629.jpg'>

