1. From the hardness point of view, 18K gold has a high hardness, which can be used for setting various gems and is not easy to deform and wear. While 18k hard gold has higher hardness and wear resistance, and is suitable for making all kinds of jewelry, which is not easy to deform and damage.
2. From the technological point of view, 18K gold usually adopts the traditional manufacturing technology, and its style is flat and not solid. 18k hard gold adopts modern special technology, with diverse styles, strong three-dimensional effect and stronger decorative effect.
3. In terms of value, although the purity of both of them has reached the standard of pure gold, the manufacturing cost of 18k hard gold will be higher because the manufacturing process is more complicated.