1. Excellent quality: The pearls of Perot Jewelry are of excellent quality, such as large size, good shape and beautiful color. Factors lead to its higher price.

2. Rarity: Some kinds of pearls are rare or difficult to find in nature, and the price is relatively high. For example, Nanyang Pearl and Black Pearl are highly regarded for their rarity and uniqueness.

3. Market demand: Due to the increasing demand for high-quality pearls, the pearls of Perot Jewelry are also in a higher market demand and the price is higher.