Everybody loves diamonds and no one looks bad in diamonds, do they? It is not actually within the scope of this piece to suggest whether diamonds are a good investment or not, but their perceived value is enormous. Instead, I want to discuss where the optimum place to buy a diamond is, because it is more importantant that you acquire your diamond from a reputable merchant with a warranty than that you think you got a decent deal on eBay by purchasing somone's grandmother's engagement ring, which may not be authentic.