MOST EXPENSIVE MATERIALS

1. https://brightside.me/wonder-curiosities/the-16-most-expensive-materials-in-the-world-188955
2. https://www.rankred.com/most-expensive-material
3. https://virtual-light.com/top-ten-most-valuable-metals-in-the-world
4. https://listsdiary.com/2016/12/08/top-6-expensive-animal-products
5. https://www.byrdie.com/the-6-most-expensive-perfume-ingredients-in-the-world
6. http://www.geologypage.com/2020/08/top-15-most-expensive-gemstones-in-the-world.html
7. https://www.fool.com/investing/general/2014/10/26/the-5-most-expensive-drugs-in-the-world.aspx
8. https://interestingengineering.com/the-10-most-expensive-materials-on-earth
9.https://www.indiatoday.in/education-today/gk-current-affairs/story/ten-of-the-most-expensive-materials-in-the-world
10. https://www.parhlo.com/20-most-expensive-food-items-in-the-world