Making a custom sapphire crystal typically involves the following steps:

1. Design: The first step is to design the shape and dimensions of the sapphire crystal according to the requirements. The design can be created using computer-aided design (CAD) software.

2. Material selection: Sapphire is a high-quality material with exceptional properties, such as high strength, hardness, and resistance to scratches and heat. However, the material selection also depends on the application requirements and the budget.

3. Growth: The sapphire crystal is grown using a process called the Kyropoulos method. In this method, a small seed crystal is dipped into a crucible containing molten sapphire. The crucible is then slowly rotated and heated to allow the sapphire to grow from the seed crystal.

4. Cutting and shaping: Once the sapphire crystal has been grown to the desired size, it is cut and shaped using precision cutting tools to achieve the required shape and dimensions.

5. Polishing: After the sapphire crystal has been cut and shaped, it is polished to achieve a smooth and clear surface. This is typically done using a series of abrasives and polishing compounds.

6. Inspection: The final step is to inspect the sapphire crystal to ensure that it meets the required specifications. This can be done using various techniques, such as optical inspection, x-ray diffraction, and electron microscopy.

Overall, making a custom sapphire crystal requires a high level of expertise and precision to achieve the desired properties and performance.