Bulgari and Cartier are both very famous luxury brands, and their product prices are usually affected by many factors. Here are some factors that may make Bulgari more expensive than Cartier:

1. Gemstone source and quality: Bulgari jewelry and watches use a large number of rare and precious gems, and the source and quality of these gems is an important factor affecting the product price.

2. Production technology and design: Bulgari has invested a lot of energy and resources in production technology and design, which makes its products have high artistic and scientific value, and correspondingly, the price will increase.

3. Brand positioning: Bulgari's brand positioning is more luxurious and upscale than Cartier's, which also leads to higher product prices.

4. Sales strategy: The price of luxury brands is not only affected by the product itself, but also by the sales strategy. For example, Bulgari may adopt strategies such as limited production and hunger marketing to maintain the uniqueness and rarity of the brand and further increase the price of the product.

To sum up, Bulgari may be more expensive than Cartier, which may be the result of a combination of factors, such as the use of rarer and more precious gems, greater investment in production technology and design, more luxurious brand positioning and different sales strategies. However, this does not mean that all Bulgari products are more expensive or of higher quality than Cartier products. When choosing to buy luxury goods, we should also make comprehensive consideration according to our own needs and budget.