The Lydians in the seventh and sixth centuries B.C. were active during the formative years of Greek culture, the period that saw the establishment of monumental architecture and sculpture in stone. Ancient Greek sources comment on their great wealth and superb horsemanship. They developed a method of separating gold and silver, which allowed them to create the first dependable coinage. Lydians harbored strong cultural sympathies with the Greeks, and in some aspects of their culture were indistinguishable from the Greeks. Little is known about the Lydians, however, and one goal of the Sardis excavation is to learn more about their culture from the material remains, the architecture and artifacts, at the site.