Anandakanda 1.2.36

1.2.36

śālāyāṃ vedikā kāryā sudṛḍhā darpaṇopamā /
iṣṭakaiḥ khacitā ramyā sasopānā salakṣaṇā //

In the laboratory, an altar should be made, very firm and like a mirror,
inlaid with bricks, delightful, with steps, and endowed with auspicious marks;