Rembrandt was a master of the Dutch Golden Age, known for his ability to manipulate light to create drama. One of his secret techniques involved 'impasto,' where he applied lead-white paint in thick, sculptural layers to catch actual light in the room. This added a three-dimensional quality to the jewels, lace, and skin in his portraits. Recent chemical analysis using high-energy X-rays revealed that Rembrandt used a rare mineral called 'plumbonacrite' in his paint mixture, which helped the thick layers dry quickly and remain stable for centuries. This combination of scientific precision and artistic intuition allowed him to move beyond the flat surfaces of his contemporaries, making his subjects feel as though they were stepping out of the darkness into the light.