Valmiki Ramayana Aranya Kanda Sarga 15 Shloka 15
Original Shlokaसौवर्णैराजतैस्ताम्रैर्देशे देशे च धातुभिः। गवाक्षिता इवाभान्ति गजाः परमभक्तिभिः।।3.15.15।।
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सौवर्णैः with gold, राजतैः silver, ताम्रैः with copper, धातुभिः minerals also, देशे देशे in different locations, गवाक्षिताः looking like windows, परमभक्तिभिः with prominent (beautiful) streaks, गजाः इव like huge elephants, भान्ति look splendid.
These mountains, with streaks of minerals like gold, silver and copper forming decorative designs, look beautiful like colourful windows, and appear like huge elephants.