During my trip on the river Elbe (see also my article from yesterday) I found some pieces of material which immediatelly got my attention: a kind of metamorphic “object” that looked almost like a… meteorite (photo width – 40 mm):

There was not only one but 8 such things on about 5 m² area and because they all looked at least weird to me, I took some samples with me at home (sizes between 1 – 5 cm). As to my knowledge, there was no active volcano in the region and recent meteoric activity can be excluded too since no reports have been recorded in this area. However, 3 out of 8 pieces contain certain amount of iron confirmed by their magnetic properties, which makes the meteoric origin at least plausible. The photo below is about 18 mm wide:

If this is indeed of meteoric or volcanic origin, than the river may have transported the little objectes from really far away in the montaneous area. Two plausible explanations may support or deny this theory: 1) these are not stones but slug fragments of smelted metal ore from the nearby mountains (but how did it get into the river?) and 2) the fragments represent some slags from either the boats’ traffic on the river or construction works. Second option seems to be the most plausible, given also the fact that the collecting site was located in the immediate vicinity of a major street.

Yes, that kind of mineral exists in nature under the name fuchsite and it is just a colored form of the common mica found in some sands (original name: muscovite). The gree mica is actually a variety of muscovite very reach in chromium (usually between 1-5%). While the common mica is grey or silver, the fuchsite form has a very nice, bright green color.

The photo above is of a little stone gathered from a stone carving artist from northern Germany who opened a galery with artistic gardening ideas (photo wide: 8 mm). One of them included fuchsite as main element due to its warm color. When the stone is exposed to sunset light it shines even stronger than under normal light, which makes the stone very attractive for colored garden fans.

Almandine is a rock-forming mineral with a deep red color (slightly purple) belonging to the garnet group. Chemically, almandine is a iron-alluminium garnet with the formula Fe₃Al₂(SiO₄)₃.

The name almandine (also known as carbuncle) comes from Alabanda, a region in Asia where the minerals were firstly found in ancient times. The term carbuncle is derived from latin and means “live coal” or burning charcoal. Almandine occurs frequently in metamorphic rocks like mica schists, similar as in the photo above taken from a small piece of conglomerate found on a beach at Baltic Sea.

Fascinated by the photographs in the previous post I searched for more stones in our small stone rack and the results we can see below. Again I don’t know much about their composition but when I’ll know more I’ll update this post so you shall come back later and check this entry.

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Yesterday we’ve been walking on the shores of a small lake not far from our house and brought back home a couple of stones. They were just regular stones but after braking them they revealed a nice texture which I though I’d share with you. Even if I know almost nothing about their composition or constituent minerals, I like very much how they look in front of the lens. All photos are 10 mm wide.

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Namibia – Erongo – 80 km E of Swakopmund (Langer Heinrich open pit uranium mine)

Sample from an open pit uranium mine. There are two types of minerals inside, both of green color. While the one on the bottom-left may be serpentine, I guess the big grain in the middle is malachite.

Yesterday I have received from a trade partner a series of nice sands from Austria, mostly areas around Salzburg and Tirol. The sands are from mountain and, as it was written on the bags, they contain a mixture of quartz, gneis, mica, feldspat and some other elements. The sand has a nice metalic shining under direct light. I have photographed only the sample 1595 AT-SZ but there are some more similar samples to follow (see also the photo gallery).

Last weekend we resumed our photography trials and got new results. The setup was slightly different because we have already been using the new Canon camera body. The lens was the same (EF 100 mm f/2.8 USM Macro) but coupled with a closeup adaptor (Marumi Achromat Macro 200). Since we used all the 21 MP of the new Canon sensor and the aperture stopped at f/16, the images came out crisp sharp even when using high magnification factors.

Oman – Musandam – Dibba, Musandam Peninsula (Indian Ocean)

I also added a new category called “Sand microphotography” with photos of sands taken using the above set-up. Just click the photo camera on the top-right of the screen to access the photo gallery.

Serpentine is a rock forming mineral found in many metamorphic and igneous rocks with chemical formula (Mg,Fe)3Si2O5(OH)4 and chemical name Magnesium Iron Silicate Hydroxide. The colour is mostly green and the crystals are translucent. In my Sand Atlas collection I have one sand with serpentine (no. 278) originating from Marine d’Albo on Corsica island in France (Ligurian Sea).