Very common Maria Theresa Thaler coin. Oman itself had the distinction of possessing the oldest Islamic coin mint in the Arabian Peninsula (Dirham in the Umayyad period) see Ref 3 for more details. Oman´s international trade required however the use of more widely recognised currencies. This explains why for centuries foreign coins like that from Venice, Austria (Theresia Thaler) and India (Rupee) played a key role.
The picture shows a Theresia Thaler with date "1780", however thalers with this date have been produced until the 1950´s...... They are called "re-strikes" Until the 1970´s it was an important currency of payment in several countries in the Middle East. For more details see Ref 1. The coin was minted since 1741. The number of Thalers minted since the death of the empress is estimated at four hundred million! Already in 1762 the Danish explorer Carsten Niebuhr reported the use of the Theresia Thaler during his travels in Yemen! The thalers are also frequently used in necklaces with the "double eagle surface" on the front. The coin has 83,33% silver.
Quite a lot of Omani silver jewelry was made from melted down Theresia Thalers, hence the very high silver content of Omani jewelry. Diameter 4 cm and weight 22 gram. In 1838 Wellsted writes on page 125:
" In the interior cities of Oman the following coins are used. All have inscriptions , but nothing bearing a likeness to any object in animated nature: A Basi, Mahmudi, Spanish dollar, Shuk"
In 1900 S.M Zwemer Ref 2 " The Rupee is the standard of value along the whole Arabian coast from Aden to Busrah. In the interior the Maria Theresa dollar has long held sway , but even that is becoming scarce among the Bedouins and they have little preference between the "abu bint" (the Rupee with the girls head) and the abu Tair (the father of a bird- the eagle on on the Austrian dollar) .