Garudapurana 1.65.45

1.65.45

niḥ svāśca kunakhaistadvadvivarṇaiḥ paratarkakāḥ /
tāmrairbhūpā dhanāḍhyāśca aṅguṣṭhaiḥ sayavaistathā //

and likewise with bad nails, they are destitute; with discolored nails, they are suspicious of others. / With copper-colored nails, and thumbs marked with barley-corns, they are kings and wealthy;