1. Diamond quality: The quality of a diamond depends on its cut, color, clarity and carat weight. Different brands have different selection and evaluation criteria for diamonds, so there will be differences between brands.

2. Diamond supply chain: Different brands have different diamond supply chains and procurement channels. Some brands buy raw stones directly from mineral countries and go through their own processing and certification process, while some brands buy finished diamonds from diamond suppliers. These different supply chains and procurement methods bring differences to the final products.

3. Design and technology: Each brand has its own design style and technology, which will also affect the appearance and quality of diamond jewelry. Different brands pay attention to different design elements or have unique technical characteristics.