Astatine. the entire planet contains only about 17 atoms of it
First of all Diamond Isn't even an element, Platinum is the most expensive element of all.
the most expensive element is a synthetic element which is Californium. It costs approximately 2.7 billion dollars per 100g. The one which isn't synthetic and the most expensive is lutetium and it costs $10000 per 100g.
Probable the atom of the element ununoctium.
The unpredictable flooding of the great rivers was the natural element that shaped Mesopotamian agriculture most directly.
diamond
Platinum is the transition element that is most commonly used in expensive jewelry due to its lustrous appearance, durability, and resistance to tarnishing.
Yes, it occurs most commonly on earth in the compound most often known as salt (sodium chloride [NaCl]).
Gold is a natural element. It is normally found as a solid metal and is relatively rare and expensive.
wind
Uranium - atomic weight; 238,02891 But now it is more correct to consider plutonium as the heaviest natural element (mass: 244 for the isotope 244Pu).
Probably a red diamond, since it is the most rare natural colour.
The International Space Station (ISS), at an estimated cost of between $35 billion to $160 billion. Darmstadtium, is an element. I'm not sure if it's the most expensive but the element only lasts a few milliseconds, making it hard to obtain and extremely valuable.