Clamps are disclosed for holding an optical element relative to a support. An exemplary clamp includes first and second arms and a member connecting the arms such that a portion of a mounting feature of the optical element is between the first and second arms. The first arm applies a clamping force toward a respective portion of the mounting feature, and the second arm includes a seat. The seat has at least upper and intermediate portions. The upper portion engages the respective location on the mounting feature. The intermediate portion is situated between the upper portion and the second arm and has a lateral thickness less than the lateral thickness of the upper portion. The intermediate portion exhibits elastic and plastic deformability sufficient for any moment applied by the clamp to the mounting feature to be limited to less than a designated peak moment, while maintaining substantially full engagement of the upper portion with the respective location.