Pearl Milkstones were a rare and precious gem. Although merfolks lived in deep seas near human settlements, very few merfolk would come into contact with humans. The society of merfolks was very elusive. Only for important diplomatic reasons would they be willing to come into contact with any other race.
A grain-sized Pearl Milkstone was valued at tens of thousands of gold coins, making it much more expensive than any other gems in the market. However, its price tag was well worth it since it was a very rare commodity as no one was brave enough to request merfolks to trade it with them. When it came to Elves, it was much easier to establish trade with them. Shrewd merchants could use precious seeds and elegant clothing as items for barter, but those shrewd merchants were helpless against merfolks.
