/usr/share/avogadro/crystals/clays/ is in avogadro-data 1.2.0-3.
This file is owned by root:root, with mode 0o755.
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/usr/share/avogadro/crystals/clays/Al2Si2O9H4-Dickite.cif
/usr/share/avogadro/crystals/clays/Al2Si2O9H4-Kaolinite.cif
/usr/share/avogadro/crystals/clays/Al2Si2O9H4-Nacrite.cif
/usr/share/avogadro/crystals/clays/Al2Si4O12Ca0.5-Montmorillonite.cif
/usr/share/avogadro/crystals/clays/Al4KSi2O12-Illite.cif
/usr/share/avogadro/crystals/clays/AlSi2O6H-Pyrophyllite.cif
/usr/share/avogadro/crystals/clays/Fe2.25Cl0.5H2.75-Fougerite.cif
/usr/share/avogadro/crystals/clays/FeSi2O6H-Nontronite.cif
/usr/share/avogadro/crystals/clays/Lepidolite.cif
/usr/share/avogadro/crystals/clays/Mg2Al2SiO9H4-Amesite.cif
/usr/share/avogadro/crystals/clays/Mg3(O12Si4)H2-Vermiculite.cif
/usr/share/avogadro/crystals/clays/Mg4Si6O22.82H13.64-Sepiolite.cif
/usr/share/avogadro/crystals/clays/Mn1.854Fe1.656Mg0.537Si0.953O9H4-Guidottiite.cif
/usr/share/avogadro/crystals/clays/Zn2SiO5H2-Hemimorphite.cif