Valmiki Ramayana Aranya Kanda Sarga 43 Shloka 31
Original Shlokaधनानि व्यवसायेन विचीयन्ते महावने। धातवो विविधाश्चापि मणिरत्नसुवर्णिनः।।3.43.31।।
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महावने in the huge forest, व्यवसायेन with great effort, धनानि wealth, मणिरत्नसुवर्णिनः gems and gold etc, विविधाः of variety , धातवः precious minerals, विचीयन्ते will be collected.
From huge forests a variety of mineral wealth consisting of gems, stones and gold are collected with great effort.