The value of natural diamonds used to be determined by their beauty, but it seems now the more expensive the stone, the better. Before Cubic Zirconia (CZ), Diamonds did not have a rival in the market. But now, since CZ is potentially more beautiful than diamonds, the parameters for beauty have changed.
Original source: https://www.pandkjewelry.com/blog/everything-you-need-to-know-about-cubic-zirconia-rings/
Original source: https://www.pandkjewelry.com/blog/everything-you-need-to-know-about-cubic-zirconia-rings/