Weighing in at $600 an ounce, RéVive Intensité is one of the most expensive and prestigious in a market full of expensive and prestigious skin moisturizers [source: RéVive]. Designed to erase wrinkles by enhancing facial volume and plumping skin cells, the key ingredient is the keratinocyte growth factor (KGF), a chemical that increases cell growth in the skin, mouth and intestines. KGP is reputed to help cells multiply up to eight times faster than normal. The human body produces growth factors naturally to heal wounds, but clinical studies have shown that even artificial KGF, when applied topically, can make second-degree burns heal faster [source: Gisquet].
Manufacturing a substance that can accelerate the healing process is an exciting idea, especially for cosmetics companies that are always looking for ways to revitalize old or damaged skin. But there's a catch. One of the reasons that the Intensité Voluminizing Serum is so expensive is that KGF is extremely difficult to produce -- a single pure gram of it is worth about $4 million, making it one of the most expensive substances on the planet [source: Singer].