Platinum and Platinum-Palladium Prints
Invented in 1873, the platinum print is made on paper sensitized with iron and platinum salts, placed (usually) in contact with a negative, exposed and then processed to produce an image of fine particles of platinum. A range of image hues can be achieved by varying aspects of the processing. Platinum images, held in the surface fibers of the paper, are permanent and highly detailed, with a wide tonal range and a velvety, matte surface. Use of the process waned during World War I when platinum's cost rose, leading to the use of palladium. With their distinctive aesthetic, both materials enjoyed a renaissance in the latter decades of the twentieth century and are still used today by some photographers who prepare their own papers.