Zabargad Island, located in the Red Sea off the southern coast of Egypt, is known for its unique geological features. The island is composed of peridotite, a coarse-grained igneous rock that is rich in beautiful blue peridot gemstones. With an area of 1.74 km2, Zabargad is the largest island in the archipelago in this bay and is often referred to as a desert island due to its lack of fresh water and limited biodiversity.
Despite its barren landscape, Zabargad Island has a rich history of gemstone mining that dates back over 3,500 years. In ancient times, peridot gemstones were collected from the island and used as jewelry for Mediterranean kings. The rock found on the island’s surface was initially thought to be topaz, leading the Greeks to call the island “Topazios”. However, scientists have since identified it as peridotite, which contains olivine and pyroxene minerals that can form peridot gemstones.
The formation of peridotite on Zabargad Island is a result of deep geological processes that occurred millions of years ago. Buried in the Earth’s upper mantle at a depth of over 150 km, the peridotite cooled and hardened before being pushed to the surface through tectonic plate collisions. The island, situated near the Red Sea Narrows, remains above tectonic activity due to its location on a mid-ocean ridge dividing the African and Arabian plates.
Gemstone mining on Zabargad Island continued into the early 20th century but came to a halt when the Egyptian government nationalized the country’s mines in 1958. Today, the island serves as a reminder of its rich geological history and the stunning peridot gemstones that have been prized for centuries.