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PhotosPhlogopite?

28th Mar 2024 04:34 UTCBruce Cairncross Expert

Magnetite

Palabora Mine, Phalaborwa, Ba-Phalaborwa Local Municipality, Mopani District Municipality, Limpopo, South Africa

Hi Steve.

The faint green colour of the crystal suggests it might possibly be clinochlore from Palabora.

28th Mar 2024 21:17 UTCRalph S Bottrill 🌟 Manager

Phlogopite is commonly green, but I am unfamiliar how it looks at this location. But muscovite (including var. fuchsite) is also listed for the mine, so the original designation may be correct?

29th Mar 2024 20:57 UTCSteve Sorrell Expert

It may be Ralph. But even the first ID would have been a visual one.

29th Mar 2024 00:38 UTCDemetrius Pohl Expert

Possibly iowaite. John Glidden, mine geologist at Palabora, had quite a number of pieces that looked very similar.

29th Mar 2024 19:55 UTCRalph S Bottrill 🌟 Manager

That’s a good suggestion Demetrius, it fits with the magnetite association.

29th Mar 2024 20:55 UTCSteve Sorrell Expert

Thanks Demetrius. I do have an iowaite from this location. I'll compare it with that one.

30th Mar 2024 20:21 UTCMark Heintzelman 🌟 Expert

Clinochlore also has a common association with magnetite, so . . .

31st Mar 2024 01:30 UTCSteve Sorrell Expert

I don't believe that it is iowaite now that I have had a good look at a different specimen that is. But I will try Ben's suggestion if I can.

29th Mar 2024 20:23 UTCJosé Zendrera 🌟 Manager

Message sent to the uploader.

29th Mar 2024 20:58 UTCSteve Sorrell Expert

Thanks Bruce. Definitely a possibility. I am struggling with how to label this one! ☹

29th Mar 2024 21:08 UTCBen Grguric Expert

Phlogopite, biotite etc fragments should show some elasticity when bent, chlorite and iowaite will stay bent. Put a drop of HCl on iowaite and it will slowly dissolve and the drop will turn greenish brown after 10 minutes or so. As there is often some carbonate in iowaite (forms a series with pyroaurite) you might see some weak bubbling initially.

31st Mar 2024 01:29 UTCSteve Sorrell Expert

Thanks Ben