A method of fabricating a platelet of a monochromator for X-ray photoelectron spectroscopy, the method comprising: placing a crystal (202, 302, 402) on a stage of an X-ray measuring apparatus, the crystal having a top surface (206, 306, 406); measuring, by X-ray reflection, an orientation of a crystal plane (210, 3010, 410) of the crystal, the crystal plane beneath the top surface of the crystal and having a primary axis; measuring, using an autocollimator, a surface angle of the top surface (212, 312) of the crystal by measuring a light beam reflected from the top surface of the crystal; wherein measuring the orientation of the crystal plane of the crystal and measuring the surface angle of the top surface of the crystal comprises performing first and second X-ray reflection measurements and first and second autocollimator measurements at approximately 180 degrees to one another; determining an angle between the top surface and the primary axis of the crystal plane of the crystal; if the angle between the top surface and the primary axis of the crystal plane of the crystal is approximately normal, fabricating a monochromator comprising the platelet; and if the angle between the top surface and the primary axis of the crystal plane of the crystal is non-normal, removing at least a portion of the top surface of the crystal to provide a modified crystal having a second top surface; measuring, by X-ray reflection, an orientation of a crystal plane of the modified crystal, the crystal plane beneath the second top surface of the modified crystal; and, while measuring the orientation of the crystal plane by X-ray reflection, measuring a surface angle of the second top surface of the modified crystal by measuring a light beam reflected from the second top surface of the modified crystal; and determining an angle between the second top surface and the crystal plane of the modified crystal. placing a crystal (202, 302, 402) on a stage of an X-ray measuring apparatus, the crystal having a top surface (206, 306, 406); measuring, by X-ray reflection, an orientation of a crystal plane (210, 3010, 410) of the crystal, the crystal plane beneath the top surface of the crystal and having a primary axis; measuring, using an autocollimator, a surface angle of the top surface (212, 312) of the crystal by measuring a light beam reflected from the top surface of the crystal; wherein measuring the orientation of the crystal plane of the crystal and measuring the surface angle of the top surface of the crystal comprises performing first and second X-ray reflection measurements and first and second autocollimator measurements at approximately 180 degrees to one another; determining an angle between the top surface and the primary axis of the crystal plane of the crystal; if the angle between the top surface and the primary axis of the crystal plane of the crystal is approximately normal, fabricating a monochromator comprising the platelet; and if the angle between the top surface and the primary axis of the crystal plane of the crystal is non-normal, removing at least a portion of the top surface of the crystal to provide a modified crystal having a second top surface; measuring, by X-ray reflection, an orientation of a crystal plane of the modified crystal, the crystal plane beneath the second top surface of the modified crystal; and, while measuring the orientation of the crystal plane by X-ray reflection, measuring a surface angle of the second top surface of the modified crystal by measuring a light beam reflected from the second top surface of the modified crystal; and determining an angle between the second top surface and the crystal plane of the modified crystal.