What is the world's most expensive nut?

Macadamia nut: the most expensive nut in the world, with the hardest shell to break. These exotic nuts are rich in vitamins, minerals, fiber, antioxidants, healthy fats and have a rich, buttery flavor. Although they originated in Australia, the trees' requirements for a warm climate, abundant rainfall, and nutrient-rich soil make Hawaii the best place in the world to grow them commercially. The reason walnuts are rare and somewhat expensive is that they require a good amount of attention from bees to be pollinated naturally, without which trees never produce nuts.

While many of them are cheap, even the most popular nuts can be expensive health foods that get more expensive the harder it is to get, grow and store them. There are ten different types of macadamia trees in the world, but only two of these species produce nuts and don't start producing until seven or ten years after they've been planted.