The Tibetan plateau was a geologic feature on Earth in Tibet on the Asian continent. The plateau was located on the northern side of the Himalayan mountain range, which featured the point of greatest altitude on the planet, Mount Everest.
In the holoprogram Julian Bashir, Secret Agent, Dr. Hippocrates Noah acquired precious jewels such as rubies from the hydrothermal deposits located on the Tibetan plateau. The deposits contained large amounts of chromium, which in turn accumulated on the rubies, giving away their original location. (DS9: "Our Man Bashir")