One gram of Antimatter cost about $62.5 trillion making it the world's most expensive material. To produce just 1 gram of Antimatter, all of mankind will have to work for about a year nonstop. NASA estimated that 1 gram of antimatter would cost $62.5 trillion, but today it cost close to $90 trillion.
Why Do We Need To Create Antimatter ?
Maybe you want to create antimatter because it will make you very rich, with $90 trillion for every gram that's a big chunk of money (don't try it, it will be destroyed the moment it makes contact with ordinary matter), but the real reason why scientists are creating antimatter is to study it since we cannot find antimatter around us, so we have to create it in order to study its properties. In the future, we might want to create it for the vast applications it could have and impact our technological advancement.
How To Create Antimatter?
Based on Einstein's equation E=mc^2 it would need 25 million billion kWh to make only one gram of antimatter, to put that into perspective, in the whole history of CERN's antimatter production, it only made less than 10 nanograms. Antimatter is the most expensive material in the world because it needs a lot of energy to be created and a lot of work.
To create antimatter, scientists need to transform energy into mass. They put a lot of energy into a very small area of space, matter-antimatter pairs are produced, each particle and its antiparticle are created into pairs, proton-antiproton is an example of matter-antimatter pairs.
Now, what if you want to create a specific particle-antiparticle pair, like proton-antiproton for example, or electron-positron pairs? The energy that you put into that small space should be equivalent to the mass of the specific particle that you want to create. For example, if you want to create proton-antiproton pairs you need to put more energy than the case for creating electron-positron pairs because protons are heavier than electrons. After they create the particle-antiparticle pair, scientists separate the matter from the antimatter at the laboratory using magnetic fields and take one antiproton particle with one positron (antielectron) particle, they combine them to make one antihydrogen atom that is stored in a special technique that I talked about here: