Our Geo Quiz is a bit nutty. Literally.
We're talking about pistachios. The roasted beige nuts crack open to reveal a greenish, tasty seed inside.
They show up in ice cream, baklava, and biscotti.
It turns that pistachio trees are cultivated in quite a few places around the world, from California all the way to Tajikistan in Central Asia.
But two countries seem to dominate the very competitive global market for pistachios: the US and Iran.
So Washington and Tehran may disagree on everything from human rights to nuclear technology. But they both seem to agree – pistachios are a key national export.
The question is: Which city in Iran is considered the heart of Iran's pistachio industry?
The answer is the city of Rafsanjan in Kerman Province, Iran.
Iran and increasingly the United States dominate the global trade in the tasty green nuts. But curiously Iran has just banned the export of pistachios.
The World asked Kamran Dadkhah, an economist at Northeastern University, to explain why Iran's government would ban the export of pistachios which are among Iran's top non-oil exports worth an estimated $1.5 billion a year to Iran.