1. composition: agate belongs to silicate minerals with time, and its main component is silicon dioxide (SiO2), usually containing some impurities such as iron oxide, which is yellow or orange. Topaz refers to the yellow timely gem, which belongs to a kind of jade containing iron oxide.
2. Color: The color of yellow agate is usually dark yellow, light yellow or orange yellow. Topaz is yellow in color, but it can be varied, including dark yellow, light yellow, amber and so on.
3. Features: the hardness of agate is relatively high, generally around grade 7, and it is relatively wear-resistant. The hardness of topaz is relatively low, generally below grade 6, and it is easy to be scratched or scratched.
4. Use: Yellow agate is usually used for carving jewelry or ornaments, beading or accessories. Topaz can be used not only to make jewelry, but also to make jade articles, such as carvings, sculptures and jade articles.
To sum up, agate and topaz are different in composition, color, characteristics and uses.