Synthetic rubies saw a price crash as mass production surged in 1900s

On December 5, 1906, a jeweller advertised natural rubies at $125 per carat and scientific rubies at $12, claiming both were genuine. By 1907, producers were making an estimated 5 million carats of synthetic rubies annually. Their prices fell sharply, while fine natural rubies continued fetching 1,000-2,000 francs per carat, according to a historical account.