Some flowers, however, are not just rare but also incredibly expensive due to their uniqueness, difficulty in cultivation, or limited availability. People all over the world have always been crazy ...

Harvesting saffron requires a lot of physical labor to get the flowers from the field to final ... and color make it the most expensive spice in the world. It's used in kitchens across the world ...

So just how is it made, and what makes it so expensive? Phan Thi Thuan's family ... Each thread of lotus silk starts with the stem of the lotus flower. The lotus is Vietnam's national flower ...