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Identity HelpInclusions in Zambian Amethyst

2nd Dec 2019 15:06 UTCAymeric Longi

Greetings everyone,

A year ago (my, already!) I had the opportunity to sift through a kilogram of tiny Amethyst crystals from Serenje, Zambia. Out of it I was lucky to pull a small set of tiny crystals bearing some real beautiful inclusions, which identities I'm wondering about...

About the acidular ones, I first thought about Rutile of course, but I'm wondering if Lepidocrocite could be in there.

The metallic ones are quite intriguing, could it be Pyrite ? If the upper side looks irregular underneath is totally flat and smooth almost looking polished and while the irregular side is of a pyrite-like golden sheen the other is more of a metallic grey. In the second crystal it nearly forms a phantom.

All crystals are about 1cm tall, give or take a couple of mm.

Cheers!

2nd Dec 2019 15:10 UTCAymeric Longi

Inclusions in this crystal show a bright red colour under transmited light, otherwise they're of a dark blue-ish metallic hue with the larger tip (closer to the surface of crystal) sometimes shifting to a light, pale grey-ish hue. They're all radiating from the core of the crystal.

2nd Dec 2019 15:11 UTCAymeric Longi

One of the crystal with supposed Pyrite inclusions.

2nd Dec 2019 15:11 UTCAymeric Longi

The crystal with "Pyrite phantom"

2nd Dec 2019 15:14 UTCAymeric Longi

And just for the pleasure to share, probably the most beautiful crystal of the lot, so colourful! This one is larger, about 2,5cm tall.

Thanks anyone for any insight,

Cheers!

2nd Dec 2019 15:19 UTCAlfredo Petrov Manager

Goethite, Amethyst

Rio Grande do Sul, Brazil

The golden-brown divergent needles in the first two photos is probably goethite, like this one from Brazil. The platy inclusions in the second photo are probably hematite.

4th Dec 2019 11:47 UTCAymeric Longi

Greetings Alfredo,

Thanks for the insight i hadn't thought about Goethite indeed.

About the platy ones, can hematite have a golden colour ? It doesn't show very well on the photos but they are of a golden Pyrite-like colour (well, only on their upper side...).

3rd Dec 2019 02:14 UTCStephen C. Blyskal Expert

At a recent mineral show (Houston, November 2019), I picked up three amethyst scepter crystals with inclusions like the ones your photos show. The dealer said they came from the border of Zambia and Zaire (Dem. Rep. of Congo). They are amethyst and smoky quartz on a milky quartz stem. Is this a known new location in Mindat? The dealer said he got them at Tucson in 2019.

4th Dec 2019 11:55 UTCAymeric Longi

Greetings Stephen,

I know that Citrine is found in this border area but I've never heard before of the type of material you describe coming from there. Actually, from your description it sounds a lot like what comes out of the Chibuku mine in Zimbabwe's Zambeze valley.

27th Jan 2020 03:53 UTCStephen C. Blyskal Expert

Aymeric,

This is a photo of the amethyst I was telling you about. I don't have any close up photos of the inclusions yet.

5th Dec 2019 15:00 UTCcascaillou

First, second, and fifth picture are goethite. Typical features of goethite inclusions include "closed-fan-like" sprays and/or "hook-like" terminations of individual needles.

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