In normal use, it will not be scratched. The specific reasons are as follows:sapphire case watch

1. In fact, the sapphire used in watches is not expensive natural sapphire, but authentic artificial sapphire, commonly known as corundum. Its chemical composition is alumina (Al₂O₃) with a hardness of 9 Mohs hardness, second only to diamond. Sapphire has high strength, scratch resistance and high hardness. Watches made of sapphire have higher shock resistance, sealing and strength than other materials.

2. Sapphire has excellent optical properties, mechanical properties and physical and chemical properties. Its advantages of high strength, high hardness, erosion resistance, and light transmission bandwidth have become the most widely used new materials.

3. Many sapphire crystal mirrors are coated with multiple anti-glare coatings to avoid refraction after receiving light. The multi-layer sapphire crystal can disperse the light source, especially under direct sunlight, to give full play to its effect, so that the wearer can still read clearly under direct sunlight without hindrance.

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