For the Love of Dendrites

Hi All,

This thread is being dedicated to the lovely form of dendrites. Initially this began as an appreciation of manganese oxides, however I invite any kind of dendrites to be shared here. In addition since dendrites are well suited for lapidary purposes and are poplular as such, these are also welcomed to be shared here.

Here are a few to start the parade. I left out Solnhofen deliberately since I am sure many of you would have wonderful ones to contribute and I would love to see them.

This first one is from Utah, USA, if anyone knows a more specific location please let me know.
Approx 10 x 9 cm




Rockydale Quarry
Roanoke, Virginia, USA
label indicates collected 7/11/1996
6 x 4 cm



Matachewan,
Ontario, Canada
6 x 2cm

A few more...

Dřínová, Tišnov, Moravia, Czech Republic
Czech Republic
7.8 x 5.5 cm



Some lapidary items...

Cuprite Dendrites in Pectolite (larimar)
Dominican Republic
2 x 2 cm



Dendrites in Chrysocolla with Malachite
location unknown
18 mm x 14 mm

Nice idea, Stephanie. Here are two specimens from Solnhofen. The first, as regards of the dendrites, is not exceptional but agreeable; a single, isolated, well defined and almost symmetric "branch". This is an occasion, however, to show a very nice Saccocoma pectinata (on the left), a probable larval crinoid typical of this place. Its diameter is 26 mm.

The second specimen is an ammonite (diameter 30 mm) crossed by well defined dendrites. I hope you like it.

Better to be just than good (Kempis)

Stephanie,
Why don't you write an article about dendrites? At the very least you should write up a better definition for our glossary than the one we have and show some more pictures of them.

Rock Currier
Crystals not pistols.

I bring a bit more to the fantastic world of the dendrites
I think for many, was the first samples, we began to captivate.
Here is a copy of manganese oxides from Jalapa Mine in El Molar, Tarragona, Catalonia, Spain.
Greetings to all.
Agustin Agudo Espinosa.

... and some manganese dendrites from Portugal. Greetings, RN

Beautiful examples and great topic! I hesitate to put this here because I am of course quite dubious that it's authentic. It appeared in Mineral Digest (vol. 5, Winter 1973) in an article by Roger Caillois, and well, it's interesting. The caption said it is limestone and the source is unknown and there was nothing else about it in the text. I'm curious if anyone has seen this piece and knows anything more about it.





Edited 2 time(s). Last edit at 08/19/2012 02:24PM by Kelly Nash.

This appears to be a dendrite of hematite. Perhaps it is hematite after a Mn oxide, but the rim of normal-appearing Mn dendrites around the hematite suggests the hematite was original. This was found at a fossil quarry in shale of the Middle Cambrian Wheeler Formation, House Range, Millard Co., Utah. There are trilobites on bedding surfaces in this piece.





Edited 1 time(s). Last edit at 08/19/2012 03:01PM by Norman King.

Steins Pass, New Mexico, north side of I-10, self-collected.

Great stuff everyone! Glad to see there is interest. Kelly, that piece would definitley require more investigation.

Rock, I will eventually put together an article, would like to see what interesting things may turn up on this thread in the meantime.

regards,
stephanie

Now an example of the Canary Islands, dendrites of manganese oxides, found on the road near the village of Toto on the island of Fuerteventura (basal complex).

A.Agudo Espinosa.

Kelly,
I bet 99,99 % that this is not a dendrite neither a limestone specimen. It seems man made something like a drawing inspired in a limestone landscape and in the dendrites effects. Buildings, people, trees, birds, all in the right place... not natural for me.
Cheers



Edited 1 time(s). Last edit at 08/19/2012 08:20PM by Rui P Nunes.

Glad to hear that Stephanie...I look forward to reading that article as I have no idea what these beautiful specimens are or how they came about etc....thanks
John

Hi Sthephanie

Some Dendrites of my collection : [www.mindat.org]

Regards.

Martins da Pedra

Rui, Those are magnificent. Could you please post more pictures from your collection?

Stephanie, do these fit the definition of mimetoliths?

While I don't have any worthy manganese dendrites, this fluorite pattern is reminiscent of dendrites.
-Dean Allum




Edited 1 time(s). Last edit at 08/19/2012 08:17PM by Dean Allum.

Thanks all for the continued contributions, hope everyone is enjoying them as much as I am.

Dean, I would assume that they would qualify because they do resemble trees or ferns or such. And I do believe you have a worthy example of dendrites, and the spodumene they have formed on makes a nice contrastive canvas.

[www.mindat.org]

cheers,
stephanie

Hi Dean Allum. thanks for your comments... more three pics. Cheers

Don't forget about dendrites within/on agates. Here's one of my favorites: my dad had a junk Lake Superior agate, showing no banding or any other redeeming features. Tossing it into a bucket, it broke along its banding (which we call "peeling," as this typically occurs due to freeze/thaw cycles). Examining the two halves that had popped apart, I noticed this tiny 1cm dendrite hiding on the surface, where it had been formed in the microscopic space between the bands.

Wow, What a great thread !
I have always loved Dendrites.
This specimen has been in my collection since 1971.


Pyrolusite Dendrite
Eichstatt, West Germany

16 cm x 9 cm



Edited 2 time(s). Last edit at 08/20/2012 03:04PM by Marc Miterman (2).

Hi everyone,

I recently found some calcite crystals with distinct presumably manganese oxide dendritic growths on several of the crystal faces. I have found similar dendritic growths from several different locations, where they had been caused by solutions seeping between bedding planes, but i'm mystified how these particular dendrites could have formed. Has anyone else seen dendrites on crystal faces?

Sorry no photos at present, all my specimens are in storage.

thanks

tom goodland