Hello this is the blogger antimonite. Ive decided to start blogging on geology in English again. But not here, since blogsome screws up so much. You can fins my new blog at sandbian.wordpress.com - Its newly started and will be about mostly geology from Sweden. Hope to see old and new readers!

/Daniel

I noticed these strange formations on my vacation to the island of Gotland this summer and they baffle me. The stone is Silurian limestone. Anyone knows what they are? They are just too common to be random weathering. A trace fossil?

Im not sure what the correct English term is for it, but this is what I do for my final paper on bachelor level in geology. A petrological and mineralogical study av so called Battle axes (also know as Boat axes or axes from Corded ware culture, around 2900-2300 BC). The geological value of this is of study is limited to me learning a lot of methods for mineral and petrological identification - on a level usually more often found on a masters degree. The archaeological value of this study is to helt determine possible connections between different parts of the neolithical Europe based on what type of rock these axes are made of.I wanna learn all there is to know about petrological and mineralogical studies, so this is as good as anything else + the cool archaeological part.

Most typical axes of this type are made of diabase or basalt, found in many places in Sweden. But the ones Im going to examine (with thin sections and so on) are made of dacite, a dacite not found here. So if theres anyone out there with knowledge of European dacite locations, please let me know.

One typical battle axe, made of diabase (I think - the white spots seems to be dusty/eroded dents and cavities, difficult to say for sure). And no, of course we dont do thin sections of nice whole samples like this, but rather of broken up parts.

I just recently came back from a week long trip to the province of Blekinge here in Sweden. Its an awsome province with beautiful deep forests and I can recommend a trip to it to anyone who loves nature. But be sure to bring something against mosquitos and ticks. The humid climate near the Baltic sea makes it a paradise for ticks.

It was a course in making maps of the bedrock, the petrology and structures. Mostly we found intrusive granites and more or less gneiss and granite-gneiss with pegmatite intrusions - the most common types of bedrock in here south east of Sweden. But one unusual loose rock caught our attention.

The theory my professor gave us was that it probably was a piece of diabas with (from the intrusion loosened) megacrysts of pegmatites in it (microcline and red quartz). The area is rich in pegmatites and diabase intrusions so the theory of origin made sence, however he had never seen anything like it before and had to base this on a qualified assumption. I presume its an unusal find or has someone found anything similar? No, its not my finger…

I found a very unusual rock last fall that I have some trouble identifying. Since this being Sweden the damn glaciers of the Ice age transport rocks all over the place (or at least from the north to the south). So the provenance of the stone is basically unkown except that it must be something possible for Sweden and neighbouring countries. I have never seen anything like it here in Sweden but perhaps some of my english speaking readers out there have at least a qualified guess to offer me. It doesnt look like any sedimentary rock that Ive seen anywhere in Sweden before. I have my guess of course, but I want your oppinion on it.

As you can se from the images its some sort of sedimentary rock. It basically looks like some form of clay (or silt) stone with stripes of quarts sand in it and rich in Iron (but that could of course be something it was exposed to simply). I havent actually weighed it, but it feels quite heavy, perhaps because of the iron?. The larger granule/grain in the middle is also quartz as far as I can tell.

Update: Added two more closeups. 

Question: Is that pyrite crystals in this piece of oil shale? I picked it up on the beach on my last trip. Or is it some strange fossil? Whatever it is, why/how/when do they form like this in the shale?

Yesterday I was on a fieldtrip to the south eastern regions of Scania (which is the most southern Province of Sweden, where I live). It took me among many things to a very small village by the ocean called Simrislund. This place is interesting geological-wise since its one of few places where Cambrian quartzite is very abundat at the surface as bedrock. Most of the bedrock is smooth and grinded flat by the last iceage. Sprinkled all over the landscape and the shoreline is oilshale since this used to cover the cambrian rock but nowdays is eroded away. Further inland the shale is still intact as bedrock. The shale is also full of fossils like brachiopods and trilobites.

One other interesting aspect of the Cambrian quartzite is the human impact on it. At Simrislund there are many rocks with carvings on it from the Scandinavian bronzeage over 3000 years ago. This makes this place both culturally and geologically worth a visit.

In my collection of “things and stuff” I got one really nice object that usually makes people envious. It’s a shaft hole axe from Uppland in Sweden. It was my grandfather who in his youth found it on a field. The archaeological dating sets this axe to the middle or late Neolithic. Around 3000 BC perhaps. But I’m not sure on that, it’s been a while since I took archaeology and the making of shaft hole axes streches some time.

Geology-wise this axe is made of, what I think at least, some form of ordinary diabase. The weight, the archaeological practise of using diabase, it all tells me this at least. There’s no volcanoes in or near Uppland (which basically is mostly old igneous bedrock, granites at about 1800 Ma), so I dont think its basalt, but rather diabase. It could be imported/transported of course. But theres a lot of shaft hole axes found in Uppland so I dont think so.

At first, the axe was all nice and shiny black in colour, with some hints of olivine green even. But then I decided to wash it and under a thick layer of like 70 years of handling and showing to people (sounds better than 70 years of deposited human dirts and fats) and that revealed a more grayish dull stone with a hint of green tones. Theres also some redish spots that came out from under the filth which looks like rust almost. I’m not so sure any more of what this stone is made of in detail since no crystalline structure is visible because of the grinding and smoothing of the axe. Any suggestions? My guess is diabase and that the small cracks and holes are the result of erosion of more fragile plagioclase in a resistant matrix of augite and olivine.

Anyhow, depending how you look at it, its an 5000 year old axe or a 1800 million year old pice of rock. And its all mine, my sweet precious shaft hole axe… 

I’ve been saving this rock for a later post. But complications have made it impossible for me to examine the rock up close any time soon. All I have are these older photos below. So I can just write about it now I guess, it wont matter if I wait any longer.

It’s (supposedly) not magnetic (that rules out iron slag right?). It (supposedly) weighs about 1-2 kilos. Its about 15x10x10 cm in size. (reduced size on the photos)

I sent the photos to an geology expert a couple of years ago, before studying geology myself in the hopes of helping my (now sadly enough dead) friend in helping to identify it.

The expert just replied shortly and claimed that it “most definitely was a conglomerate”.

Im no expert, just a first year student. An amateur. But this doesn’t look like any conglomerate that I know of. Where are the pieces of rocks and granules? Shouldn’t there be at least one lousy piece of granule visible if the craters are the sockets of rocks? Are they really all loosened and gone? Doesnt sound very plaucible to me. And when I replied to the experts answer with a follow up queastion and asked how this could be a conglomerate without any visible captured parts, his stuck up pride probably got offended and he just got bored with me and didnt answer at all. I almost lost all faith in geologists that time. What an idiot. Esteemed professor emeritus of Lund university and all. Well, he didnt make that far in the academical world on being friendly to the taxpayers who payed him and his research (Publically funded universities in Sweden you know). Well enough about him.

In my, very unprofessional opinion, this looks much more like a meteorite. But according to the expert, that wasnt even an option. I really never understood why.

I know that meteorites of course are less likely to be found in comparison to just about any type of rock. I’m not stupid on that part. But I can’t get over the fact that it looks like one much more than it looks like a conglomerate.  

The rock also comes with a story (from my dead friend) that his father actually saw “a falling star” and went looking in the direction of where it seemed to have fell. Some miles away he found burned grass and this piece of rock between some cliffs at the west coast of Sweden. Around 1920 I think he said this all took place.

What does my readers say? Conglomerate? Meteorite? Iron slag? Flint? Or something else? What can you make of it just by looking at these photos (that’s all I have, its impossible for me to examine the rock itself or take better photos any time soon). Im all ears.

Got a new camera. Nothing fancy, a "Canon digital Ixus 950 is". But it had a nice macro-function so i took som new photos just for fun.

Picture below is a garnet crystal inside of a amfibolitic rock. Hornblende to be precise. Picked it up on an excursion.

Picture below is of a olivine crystal (or a couple of them of course) inside a basalt rock from a small dead "vulcano" in the middle of Scania. Age about 145 Ma. Picked it up on an excursion.

Picture below is of an ordinary sandstone heavily oxidized with iron found in an Jurassic-Trias-deposit of sand. Its composed of several layers of differently oxidized and dense sediments. Looks more strange than it is. 

The picture below is not totaly geological but still quite nice. A piece of iron slag from Uppåkra (Uppakra) Iron age settlement outside Lund (roughly 700 AD perhaps). Since I started my career with archaeology I also have some archaeological things in my possesions. Some of them I actually found myself on field training exercises like this slag and the piece of pottery below.

The picture below is of a piece of Iron age pottery from the same settlement/village.