Santorin Earth

Naturally occurring pozzolans are trass (a volcanic tufaceous rock found in the Rhineland, Bavaria and Austria), santorin earth (Greece) and the Italian pozzolans (Pozzuoli near Naples). A synthetic material with similar properties is fly ash, which is produced in hard coal- and lignite-fired power stations. 

The pyroclastic rocks, in the form of loosen deposits or consolidated formations, produced as a result of diagenetic cementations belong to the first group. They originate from the emption of magma and include sands, volcanic ash and fragments of rocks, carried away from the crater of volcano. The loosen deposit rocks from Naples and Rome, the Santorin earth from the Santorin Island, as well as the corrsolidated rocks the Rhine, Naples and Bavarian tuffs, so-called trass, are among the most commonly known. 

Santorin earth. A variety Santorin Island (Greec pozzolana cement. 

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