Why is sapphire in Taiwan Province Province so expensive?

Official website introduced that the famous jade carving artist, Taiwan Province sapphire, is expensive because Taiwan Province sapphire is also called "Taiwan Province sapphire". Its color is mostly blue-green, sky-blue or emerald green, which is very beautiful, but its transparency is poor, it is almost opaque, and it will not fluoresce or crack. Sapphire mineral resources in Taiwan Province Province are scarce, and the finished products on the market are even rarer, so the price is relatively expensive.