Blue Nile is the largest online retailer for diamonds and other fine jewellery like pearls, gemstones, silver and gold. This specialty online jeweller sells certified diamonds for affordable prices that are well below the traditional retail price, sometimes as low as 20-40% lower. Blue Nile offers the high-quality diamonds, which you will have the option to search for by carat, cut, and size so you may customize your engagement ring or gift to your exact preferences. The company has been running their simple and successful business model since 1999, and has developed a strong customer base through offering their unique online shopping experience.