Abstract: An apparatus and method for applying x-ray absorption, refraction, and/or scatter detection methods to authenticate objects. The invention can be used for the authentication of any object, such as, without limitation, artwork, antiques, currency, shipped materials, etc., by the application of a detection material that is detectable by applying x-rays. The detection material is imbedded within the object, or otherwise invisible to the human eye, IR, UV, and conventional x-ray radiography techniques. The method of this invention is particularly useful in security applications, such as for verifying the authenticity of identification documents like passports and similar identification cards.