Unearthing the Mysteries of Zabargad Island: A Journey through its Geological Wonders and Ancient Gemstone Mining History

In the Red Sea, off the southern coast of Egypt lies Zabargad Island. This island, with a surface area of 1.74 km2, is the largest in the archipelago in the Gulf of Foul. Despite its lack of fresh water and biodiversity, Zabargad Island is rich in geology, specifically peridotite- a coarse-grained igneous rock that contains beautiful blue peridot gemstones.

In ancient times, these gemstones were highly sought after and used as jewelry by Mediterranean kings. Evidence of mining on the island dates back more than 3,500 years to ancient Egypt. While the Greeks believed it to be the source of topaz and called it “Topazios,” scientists have identified it as peridotite- rich in olivine and pyroxene. Inside this layer, olivine can form the gemstone peridot- known for its brilliant yellow-green color.

Peridotite forms deep in Earth’s upper mantle at depths over 150km and was pushed to the surface through geological processes millions of years ago. Due to its proximity to the Red Sea Narrows- an area of tectonic activity-the island remains above the center of geological movements. Although gemstone mining on Zabargad Island continued into the early 20th century, it declined after nationalization of mines by Egyptian government in 1958.