Valmiki Ramayana Kishkindha Kanda Sarga 40 Shloka 49
Original Shlokaस्वादूदस्योत्तरे देशे योजनानि त्रयोदश।।4.40.49।। जातरूपशिलो नाम महान्कनकपर्वतः।
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स्वादूदस्य of the ocean of tasty water, उत्तरे देशे the north direction, त्रयोदश thirteen, योजनानि yojanas, महान् huge, कनकपर्वतः golden mountain, जातरूपशिलो नाम called Jatarupasila.
'Thirteen yojanas to the north of this ocean of pure waters is a huge golden mountain called Jatarupasila.