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[zbhjzm]

Super thin hematite inclusions in amethyst:

[Tobi]

[zbhjzm]

[braulioff]

I´ve been told most of these inclusions are goethite.

[zbhjzm]

[John S. White]

I would guess goethite. Hematite tends to be red in color in very thin crystals. And although some of these crystals are reddish, they are not the red of hematite.

[zbhjzm]

Actually the specimen is only partly purple, most of the inclusions are in the colorless part of the quartz and they are indeed red.
Though the inclusions are super thin ,still they look exactly like the hematite inclusions in the so-called " strawberry quartz".

[kakov]

Fantastic images! I am specially fan of the one with pampas landscape like goethite inclusions.
As “traditional” mineral collectors often feel certain aversion against the cutting and polishing of stones, the “inclusion world” falls out of our sight. But it is truly fascinating, so thanks a lot for sharing such images here! And please continue with this good habit (I have seen you have posted stuff previously as well).

[zbhjzm]

[John S. White]

Sorry to have to disagree with you but to my eye the inclusions in the two quartzes are not "exactly" alike. Those in the so-called strawberry quartz are typical hematite red while the others, assuming that the color in the photo is true, are not. And judging from your photos in the first postings they are quite varied and range from reddish to brown, something I would not expect to see with hematite.

[zbhjzm]

[alfredo]

To my eye, the first two photos do look like hematite inclusions, especially the red "stems" of those dendritic aggregates. Apparent variation in color towards the tips could be caused by some thin film effect between the hematite and the quartz, ie some surface film on the hematite or gap between the hematite and the quartz. Thin films are very difficult to check; we really don't have good technology to analyze thin films yet.

[John S. White]

Hate to come on like a pedant but I can claim a certain amount of expertise on this subject as it has been a focus of quite a lot of study on my part and I am also particularly reluctant to challenge anything that Alfredo states, but the color of very thin hematite is quite distinctive and constant in my experience whereas that of goethite is not. Apart from the fact that the red in your photos is not a hematite red, the very fact that your photos show a wide range of color is, in my view, evidence enough to rule out hematite.

[alfredo]

John, Would Raman spectroscopy work through quartz to distinguish the various iron oxide species, or would the quartz interfere?

[zbhjzm]