1. The appearance of a fake ruby is frequently lackluster. These stones are clear, yet they lack brilliance. Note that if your ruby is dark red, it could be a garnet. To make sure of its authenticity, examine the evenness and uniformity of the colors throughout the stone.
2. Fake rubies frequently have imperfections and impurities spots. However, not all genuine rubies are flawless. Some knowledge in gemology is required to determine whether or not you are looking at a real ruby. Scratches, streaks, nicks, and minor scuffs are examples of superficial flaws. Just to get an idea, internal defects or inclusions are classified as follows: solid inclusions, which are generally crystals of different shapes, such as lamellar, or elongated crystals, negative crystals, canals, or gaps, "givres," and growth peculiarities.
3. Rub your gemstone gently against a hard, smooth surface, such as ceramic or clear glass. The stone will almost always scratch the surface. What you are looking for, however, is whether or not your ruby has left a red trace on the rubbed surface.