Garudapurana 1.69.25

1.69.25

cintyā na tasyākarajā viśeṣā rūpe pramāṇe ca yateta vidvān /
na ca vyavasthāsti guṇāguṇeṣu sarvatra sarvākṛtayo bhavanti //

The wise man should not consider particularities arising from their mines, but should examine their form and size; / nor is there any fixed rule regarding qualities and defects: all shapes occur everywhere.