Quick Links : Mindat手册 The Rock H. Currier Digital Library Mindat Newsletter [Free Download]

主页关于 Mindat Mindat手册 Mindat的历史版权 Who We Are 联系我们于 Mindat.org刊登广告

捐赠给 Mindat Corporate Sponsorship 赞助板页已赞助的板页在 Mindat刊登广告的广告商于 Mindat.org刊登广告

Learning Center What is a mineral?The most common minerals on earth Information for Educators Mindat Articles The Elements The Rock H. Currier Digital Library Geologic Time

搜索矿物的性质搜索矿物的化学 Advanced Locality Search 随意显示任何一种矿物 Random Locality 使用minID搜索邻近产地 Search Articles 搜索词汇表更多搜索选项

Mindat手册添加新照片 Rate Photos 产区编辑报告 Coordinate Completion Report 添加词汇表项目

Mining Companies 统计会员列表 Mineral Museums Clubs & Organizations 矿物展及活动 The Mindat目录表设备设置 The Mineral Quiz

照片搜索 Photo Galleries Search by Color 今天最新的照片昨天最新的照片用户照片相集过去每日精选照片相集 Photography

Discussions

💬 Home 🔎 Search 📅 Latest

╳Discussions

💬 Home 🔎 Search 📅 Latest

Groups

Recent Images in Discussions

GeneralWhat is it?

17th Jan 2012 14:58 UTCJim Andersen

It measure 6" X 12" "pings" when flicked with a finger like glass, the pockets have long slender micro yellow crystals eg; quartz? It is also very heavy and is non-magnetic.... Fulgerite? Manganese? Bog Iron? anyone care to take a shot? I would love to ID this thing! Thanks, Jim

17th Jan 2012 17:16 UTCAlfredo Petrov Manager

Break a crumb off and put it into acid - even vinegar or lemon juice will do. See whether it bubbles.

17th Jan 2012 18:20 UTCMichael Hatskel

A fossilized baby croc? :-D

17th Jan 2012 18:45 UTCChristian Auer 🌟 Expert

A fulgurite in my opinion.

17th Jan 2012 18:54 UTCZach Richard

It may be a fulgurite, but check a piece in acid - it could be likely that those yellow crystals are calcite. I know of some Florida specimens like this where the sandstone has calcareous pockets - especially fort drum/rucks pit stuff. They are also very oddly shaped like the one you have.

17th Jan 2012 18:58 UTCJim Andersen

Very hard as no pieces just crumb off. I would have to hammer or use pliers. I applied acid with small paint brush on the back, no foaming. Here are some better photos. Very dense grainy matrix,with marble sized pockets in situ. Bog manganese or

copralite have pockets in it?

17th Jan 2012 19:03 UTCZach Richard

Slag?

17th Jan 2012 19:14 UTCJim Andersen

Looks similar to slag but not, the xtals in the voids look like stained quartz due to their termination but some appear to have a sharp barbed wire like angle.

17th Jan 2012 20:26 UTCWayne Corwin

Jim

can you get ant close-up's of the pockets or crystals?

sure would help. are he insise of any of the pockets glassy?

do you have any clue as to where it came from?

Wayne

17th Jan 2012 21:15 UTCJim Andersen

Wayne, I have had that rock almost 25 years,it came from a old now deceased prospector, Wally Howe from Campton, N.H. Wally did all his picking in the northeast so it probally came from not too far away....Nope no glassy interior on any of the voids just lots of tiny xtals that a 15x lens has a hard time with! Maybe weathered out horneblende vein..... or basalt??

17th Jan 2012 23:12 UTCPaul Brandes 🌟 Manager

Looks like some sort of funky iron concretion to me...

17th Jan 2012 23:40 UTCCraig Mercer

Some different photo angles will most likely give it away ;-)

18th Jan 2012 03:30 UTCNorman King 🌟 Expert

Notice that there are pits in some of the broken ends. Actually, these are probably canals. This does indeed look like an iron oxide concretion, specifically the kind called a rhizocretion. Rhizocretions form in soil around root systems. Over time, root systems develop a random-looking pattern such as you possibly have. The canals are where the root material was, and the rest of the mineral matter precipitated around the root.

That's one possibility.

See the attached photo of rhizocretions from San Salvador Island in the Bahamas. These happen to be carbonate, but iron oxide is just as common. The main thing is the form.

18th Jan 2012 13:42 UTCJim Andersen

Wayne here is a little more detail on the voids. I think Norm is almost dead on .

18th Jan 2012 13:48 UTCWayne Corwin

Looks like he knows his stuff,,, Sure looks like it.

Go to top of page