What is the difference between old and antique?

Old describes something of considerable age relative to others of its kind or other stated viewpoint. As a general rule of thumb antique describes something of age usually greater than 50 years and to be of a certain value. Value is discerned by its state of rarity, age, history and how well sought after it is within the current market among buyers. If something is old, but has little or no value, it is not of thought of as antique.