| | Book (edition) | tin-bearing ring granite bodies of the Jos Plateau, Nigeria, mainly at Timber Creek, near Jos, and also at...topaz crystals in Delimi R., Bauchi State, both Nigeria. Blue aquamarine is common in alluvial gemstone...unique are emeralds from Gwantu, Kaduna State, Nigeria, which originated hydrothermally with aquamarine...volcano-intrusive ring complexes of the Jos Plateau, Nigeria, where a fine-grained cassiterite was mined from...near Bukuru, and in the Afu granite complex, near Nasarawa, Plateau State. Cassiterite occurs in some granitic |
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