Garudapurana 1.159.28

1.159.28

śarāvamānasaṃsthānā piḍikā syāccharāvikā /
sadāhā kūrmasaṃsthānā jñeyā kacchapikā budhaiḥ //

having the size and form of a saucer, such a carbuncle is śarāvikā; / burning and shaped like a tortoise, kacchapikā is known by the wise;