Valmiki Ramayana 4.27.13

गुहा द्वारे च सौमित्रे शिला सम तला शिवा ।कृष्णा च एव आयता चैव भिन्न अंजन चय उपममा॥

guhā dvāre ca saumitre śilā sama talā śivā |kṛṣṇā ca eva āyatā caiva bhinna aṃjana caya upamamā ||

Our plain-language meaning of this verse is waiting for scholar review.