I’d never invest in diamonds...worst investment ever.
Diamonds are a dog. The proof is that unlike gold, you could never resell a diamond for anywhere close to what you paid for it. Diamond values are manipulated to the extreme prices they occupy by Debeers. The mastered the art of cornering the market of a gemstone that is not all that rare.
They store an incredible amount of diamonds. They feed a small enough number of diamonds into the system annually to always ensure high prices. They can flood out competitors until they sign on to maintain the system.
Diamonds are nothing like gold.