The gold price of Sun Gold Store is relatively low, which may be related to its business model and cost structure. First of all, Sunjindian independently mines and refines gold, and there is no intermediate supplier to earn the difference, so the cost is low. Secondly, Sun's storefront is also owned by the company, and there is no rent expenditure, which further reduces the cost. These cost advantages may make Sun Jindian adopt a lower gold price to attract more customers.

Regarding purity, I'm not sure if the gold purity of Sun Gold Store is low. Purity is an important index of gold quality, but different gold ornaments may need different purity standards. If the gold purity of Sun Gold Store meets the national regulations, its low price may be due to other factors, such as the above-mentioned cost advantage.

Which is better, Lao Fengxiang, Qilu Jin Dian and Sun Store, may need to be evaluated according to specific needs and evaluation criteria. Each gold shop has its own unique characteristics and advantages, such as brand reputation, service quality, gold quality and price. Therefore, which gold shop to choose should be evaluated according to personal needs and preferences, and then make a decision by comparing the official website and customer evaluations of different gold shops.