Anandakanda 2.8.168

2.8.168

nirmalaṃ ca prabhāyuktaṃ sphaṭikaṃ śreṣṭhamucyate /
himālaye siṃhale ca vindhye revātaṭe tathā //

Clear and endowed with luster, crystal (sphaṭika) is said to be best.
In the Himālaya, in Siṃhala, and on the Vindhya and the bank of the Revā,