Why is bone china so expensive?

Why is bone china, known for its exquisite beauty and durability, often priced significantly higher than other types of porcelain? What unique qualities does it possess that make it a sought-after luxury item among collectors and enthusiasts? Could the intricate crafting process and the addition of bone ash to the clay mixture contribute to its premium pricing? Is there a significant difference in the overall quality and appearance of bone china compared to other ceramics?