Preliminary geological and geochemical characteristics of sapphire bearing rock of Chilla area, central Tigrai, northern Ethiopia
DOI:
https://doi.org/10.11606/issn.2316-9095.v24-210313Keywords:
Sapphire, Alkaline basalt, Host rock, AlluvialAbstract
Even though, Ethiopia is endowed with suitable geological setting to host varieties of gemstones, it has not yet been well investigated and explored. In Northern Ethiopia, Tigrai regional state, sapphire mineral has been extracted by traditional and artisanal miners. Chilla, which is 35 km north of Axum, is one of the sapphire’s arti-sanal mining activities has been practiced. In Ethiopia, particularly in Chilla area there is no any geological and geochemical study on Sapphire mineral and its host rocks. In Chilla area, most of sapphires are found in alluvial or eluvial deposits, making it grim to study the relationship between the sapphires and their host rocks. Here, we present preliminary geological characteristics of sapphire mineral within alkaline basalts from the tertiary Chilla volcanic terrain. Geological investigation and geochemical analysis (XRF) indicates; the sapphire mineral is hosted in tertiary alkaline basalts and occur in the contact between alkaline basalt and intrusive granite rocks.
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