Garudapurana 1.70.24

1.70.24

strehapradigdhaḥ pratibhāti yaśca yo vā praghṛṣṭaḥ prajahāti dīptim /
ākrāntamūrdhā ca tathāṅgulibhyāṃ yaḥ kālikāṃ pārśvagatāṃ bibharti //

and which appears smeared with grease, or which loses brilliance when rubbed, / and which, when its top is pressed by two fingers, displays a black tint on the sides;