Gold, silver, or diamond is not a real treasure of life. They are outer materials which are always affected by the law of impermanence.
According to a Sutra in Dirgha-Agama (The Long Discourses), the Buddha taught 500 people of the Licchavi clan Five Treasures of life that are hard to find.
Once you have found these treasures, you must value and esteem them.
What are they? The infographic below will give you a summary of the five rare treasures, based on the explanation of Thay Thich Truc Thai Minh in His regular Dharma talk on November 22, 2020.