I am a chemical engineering student and I am having trouble understanding a passage in a separation process textbook I am reading. The passage is about the preparing solids for leaching, such as grinding and crushing ores. At the end of the paragraph, the textbook states "Grinding of the particles is not necessary if the soluble material (the desired product) is dissolved in solution adhering to the solid. Then, simple washing can be used, as in washing of chemical precipitates."
I have tried researching this myself, and the only relevant information I found was if the desired product is on the surface of the solid, no grinding is needed. Is this what the textbook is trying to say? I am having a hard time understanding the wording of the textbook, especially about "solution adhering to the solid".
Reference I found: https://nitsri.ac.in/Department/Chemical%20Engineering/Leaching.pdf