बिहार के किस जिले में लौह-अयस्क का खनिज हेमेटाइट पाया जाता है ? - In which district of Bihar the iron-ore mineral hematite is found? - Bihar Ke Kis Jile Me Lauh - Ayaska Ka Khanij Hametite Paya Jata Hai ? Bihar Gk in hindi, Government Schemes Jamui question answers in hindi pdf Nawada questions in hindi, Know About Gaya Bihar Gk online test Bihar Gk notes in hindi quiz book Bhagalpur