Quoted from Central Bank of Oman

The Central Bank of Oman is pleased to announce to the public that it will put into circulation a revised banknote with additional security features of the fifty riyal denomination, starting from June 2, 2019.

This banknote will be circulated as legal tender alongside the currently circulating banknote previously issued by the Central Bank of Oman with the same security and general features, with the following enhancements:  

-New security features of the revised banknote:

obverse:

-A gold-colored security stamp in the shape of a window on the right side of the paper, showing:

1. Currency value.

2. The main entrance to the Central Bank of Oman building.

3. The bank's name in both Arabic and English.

-Its color changes from gold to blue when exposed to any light source.

• Shiny gold magnetic security thread with a color-changing zigzag line (gold to green) in the middle, intermittent and interwoven with the paper on the front of the currency.

• A security feature in the shape of a crown that changes color from gold to green when the banknote is tilted up and down.

 The currency appeared:

• A gold-colored security stamp in the shape of a window on the left side of the banknote showing the main entrance of the Central Bank of Oman. Its color changes from gold to blue when exposed to any light source.