I had a Paddle around sa Porrassa the other day https://peakd.com/hive-181335/@abh12345/igicdjwt

Wiki says it was used for Salt until the 1960's. Maybe this will enlighten us?

https://www.earthmagazine.org/article/travels-geology-mallorca-set-stone/#:~:text=Composed%20of%20dolomite%20and%20limestone,its%20northern%20and%20southern%20coasts.