【新規ポイントで出た鉱物】 好みなので出てくると嬉しいハチミツ色の水晶🍯🐝 #鉱物 #探石

鉄石英(赤石英)？？？ 水で濡らすとなかなか綺麗です✨️ #鉱物

初めて入る河川敷でポイント開拓 なんかボコボコした石 なんかの化石？ #鉱物

住宅街の中を流れる川の石を割って出た水晶 山で取れるような立派な結晶では無いけどビギナーなのでこれでもじゅうぶん満たされます☺️ #鉱物

The chemistry on this one is so odd. A snail dies and ends up in mud with no oxygen. The soft body rots. Rotting organic matter gives off phosphate, and the sediment has plenty of iron around. In most places that iron gets grabbed by sulfide and turns into pyrite, which is how you get all those shiny fool's gold fossils. But there's a narrow layer in some immature sediments, roughly the boundary where sulfate reduction stops and methane production starts. Down there the sulfide has mostly run out, so ferrous iron and phosphate can both stay dissolved long enough to find each other. What you get is Fe3(PO4)2·8H2O. Vivianite. It grows as blue green blades in the exact hollow where the animal used to live. So the soft tissue is long gone, but the phosphorus that was in it is now part of a crystal sitting inside the shell. I find that a little unsettling and also fantastic. This one is a 3.1 cm snail, possibly a naticid, so a moon snail. It's from the Kerch iron ore deposits in Crimea. That's the classic spot for vivianite in fossil shells, but most Kerch material is bivalves, and the crystals are usually blue or dark because they've already oxidized badly. A snail with green crystals that still look this fresh is the less common version. Look at the photo. Half the opening is filled with black sediment and the other half is a messy jackstraw pile of glassy green prisms. The shell itself is chalky cream with little blue stains near the apex, which I'd guess is phosphate leaking out where it didn't belong. Now the bad part. Vivianite darkens. The ferrous iron oxidizes to ferric iron and the crystals slowly go from pale green to deep blue and then close to black. The standard collector advice has always been to blame light. If I owned this I'd keep it in a dark drawer, take it out for maybe ten minutes when someone came over, and feel guilty every time I opened the drawer. Like I'd adopted a pet I'm not allowed to look at. One nerdy footnote I came across, though. A 2024 paper in Geochimica et Cosmochimica Acta tested pure vivianite and found light had basically no measurable effect on oxidation. Oxygen was the problem, and a big one. The authors still said collections should keep protecting natural specimens from light, since impurities might matter in ways they couldn't rule out. So the dark drawer stays, but now I'd put it in an airtight box too. The fully oxidized end product is called metavivianite, also known as kertschenite, and as far as I know that name comes from Kerch. So this locality has its own mineral named after the way its vivianite falls apart. Kind of grim. Link in 🧵

LABRADORITE 🇲🇬 Madagascar ゴールド系も綺麗✨️ #鉱物 #ラブラドライト

柏屋食堂 〒969-1124 福島県本宮市本宮仲町２９ 前から気になっていたソースカツ丼の有名店へようやく行けました。 とても綺麗に揚げられたロースカツに甘じょっぱいソースが程良く染み込んでいます。 肉は柔らかく、ころもはサクサクで脂身も甘みがありとても美味しかったです。 リピ確定です👍

LABRADORITE 🇲🇬 Madagascar 手軽に入手できる美しい海外鉱物のひとつ、ラブラドライト。 構造色が魅力的です。 #鉱物 #ラブラドライト