#topazios

A gem in the sea

In the Red Sea where continents are literally breaking up and a new ocean is slowing extending lies Zabargad island, a massive piece of uplifted mantle. Rocks of this exposed mantle consist of fresh, non-serpentized peridiotites, mainly made of forsteritic olivine, including gem quality peridot. Of these, the peridot was crystalized in situ (therefore very fresh) in fault cracks that could have been 25m deep. Some of them can be over 1m in size! Although peridot is quite common worldwide, such large green gem crystals are only found at Zabargad.

In ancient times the island was was mined for topaz (before the 18th century peridot was one of several things named topaz) by the Greeks and the Egyptians, who called the island Topazios. It is believed that the name topaz actually derived firsthand from the island. According to Pliny’s Naturalis Historia, the Theban queen Berenice was presented the first specimen of topaz around 300 BC. In addition to Topazios, the island is also known as Seberged, Zebirget and St John’s Island. The name Zabargad is translated as peridot in Arabic.

From below the island appears as a pillar that rises from the sea, this is due to a incredibly blue lagoon with a steep reef that surrounds the island. These cliffs plunge down 500m and are a very popular place to dive.

Our past post on gem peridot:http://tinyurl.com/pavuvbq

-OW-

Image: Courtesy of Tim Priest. The north side of Zabargad with the steep cliffs on the foreground. Note the green color of the hills.

References: http://giantcrystals.strahlen.org/africa/seberged.htm http://www.palagems.com/peridot_buyers_guide.htm http://www.palagems.com/gem_news_2010_v3.php[_