Diamonds don't simply "turn into gas" at a specific temperature. They undergo a process called sublimation, where they transition directly from a solid to a gas without passing through a liquid state.

The temperature at which this occurs is very high and depends on the pressure. Here's a breakdown:

* At standard atmospheric pressure (1 atm), diamonds sublimate at around 4500 °C (8132 °F). However, it's important to note that at this temperature, the diamond will likely react with oxygen in the air and burn.

* Under high pressure, the sublimation temperature increases significantly. This is why diamonds are able to form deep within the Earth's mantle, where the pressure is immense.

Therefore, there's no single "gas point" for diamonds. Their sublimation point depends greatly on the surrounding pressure.