Gustav Klimt, a leading member of the Vienna Secession movement, is most famous for his 'Golden Phase.' During this period, he incorporated real gold leaf into his paintings, most notably in 'The Kiss' (1907-1908). This technique was inspired by his travels to Ravenna, Italy, where he was mesmerized by the Byzantine mosaics in the Basilica of San Vitale. Klimt used gold to create a flat, decorative surface that elevated his subjects to a divine or iconic status, blending eroticism with spiritual symbolism. His work often focused on the female form and used intricate patterns influenced by Art Nouveau. Klimt’s paintings were often controversial for their overt sexuality, but they are now some of the most sought-after works in art history, with his 'Portrait of Adele Bloch-Bauer I' selling for $135 million in 2006.