Here's why:
* Size: South Sea pearls are the largest commercially harvested pearls, often ranging from 8mm to over 20mm. Larger size equates to higher price.
* Rarity: Golden South Sea pearls are rarer than white South Sea pearls, making them even more valuable.
* Luster and Nacre: High-quality South Sea pearls have a thick nacre layer and a beautiful, deep luster.
* Origin and Cultivation: These pearls are primarily cultivated in Australia, Indonesia, and the Philippines, where strict regulations and specialized farming techniques contribute to their quality and cost.
While other factors like shape, surface perfection, and matching also influence the price, South Sea pearls, especially golden ones, generally command the highest prices in the pearl market. Other pearls which also come with a high price tag are Tahitian Pearls due to their rarity and dark hues.