It is theoretically possible to cut a diamond with a water jet cutting system, but it is not a practical or commonly used method. While diamonds are extremely hard and durable, they are also brittle, making them susceptible to cracking or chipping under pressure.

Water jet cutting systems use a high-pressure jet of water to cut through materials, and while the water jet is powerful, it may not be precise enough to cut a diamond without causing damage. Additionally, the water jet would need to be paired with a suitable abrasive material to cut through the diamond, which could further increase the risk of damage or cracking.

There are other cutting methods that are better suited for cutting diamonds, such as laser cutting or wire sawing. These methods use precise cutting tools and techniques that can minimize the risk of damage or cracking to the diamond.

In summary, while it is technically possible to cut a diamond with a water jet cutting system, it is not a practical or commonly used method due to the risk of damage or cracking. Other cutting methods, such as laser cutting or wire sawing, are better suited for cutting diamonds with precision and accuracy.