Freshwater pearls come in a variety of natural pastel colors. Unfortunately, black is not a naturally-produced color of freshwater pearl. Therefore, select pearls are treated with a permanent, color-treating organic dye to create a dark coloration, similar to that found in exotic Tahitian pearls. The black freshwater pearls that undergo the treatment for us are chosen by us for their shape and luster. They are the roundest, finest-quality, color-treated freshwater pearls available.