Blue stone and Copper sulfate

Blue stone noun - Hydrated blue crystalline form of copper sulfate.

Copper sulfate and blue stone are semantically related. In some cases you can use "Copper sulfate" instead a noun phrase "Blue stone".

Copper sulfate noun - A copper salt made by the action of sulfuric acid on copper oxide.

Blue stone and copper sulfate are semantically related. Sometimes you can replace phrase "Blue stone" with "Copper sulfate", this phrases are similar.