heazlewoodite

* precrushed with a hammer in plastic bag. For all 3 samples it is possible to get 20% < 5 µm in about 5-10 minutes wet grinding-time.

* precrushed with a hammer in plastic bag. For all 3 samples it is possible to get 20% < 5 µm in about 5-10 minutes wet grinding-time.

* precrushed with a hammer in plastic bag. For all 3 samples it is possible to get 20% < 5µm in about 5-10 minutes wet grinding-time.