Fulgurite

Hey ya'll......attached are a couple of photos of fulgurites. These are from a part of North East Florida where lightning is expected to strike the beach at any time. One is of a 25 1/2 pound fulgurite and the other is of smaller, yet sizeable pieces. The sharpie pen may help with scale on those. The "Monster" fulgurite is sitting in a standard size plastic lawn chair. Kind of looks like a dragon or old man.....ok maybe not. That's just the artist in me. The best way to describe the sound that these make when struck together, is that of coral or porcelain. They are very fragile, yet durable.......yes, they have been out in the garden for a few years.
......I have one piece which, to me, resembles Osceola or some other native American chief and is about 11 inches tall. It's mounted with wire and hanging on the wall. Perhaps I should keep that one but, all of the others must go up for sale. Stupidly, some years ago, I offered the "Monster" to the Smithsonian, as a donation, and no one replied to my email. Their loss! That is before I found out that they have some monetary value.
......I must say that the reddish coloration is due to the nature of some of the beaches in Florida which are made up of broken down shell, coral, fossils and quartz. These beaches are not white but, dark tan, mixed with varying degrees of whitish quartz sand. In fact, some beaches, around this part of Florida, have open deposits of Coquina rock, with which the Spanish used to build their forts and residential foundations. There can also be found a type of red clay in pockets, here and there.
......Well, if you guys have any ideas about values and /or best places to market these fulgurites, all would be welcome. I don't normally sell my collections but, .......hard times, you know.

Thanks for your help,
Michael

These look like calcite cave formations, not fulgurites. But, to be sure, could you take a close-up photo of a broken end, to show the cross section?

Hi Michael,

Can you see or otherwise tell if any of these specimens are hollow?

Ron

No, these are not hollow and they were collected by me and my Dad some years ago, at the beach. In front of a beach access ramp, someone had driven a four wheel drive vehicle over the area of the fulgurites and many were broken up, so we gathered them up from the soft beach and put them in the truck, on blankets. I do know that not all fulgurites are hollow. The beaches here are very different from most around the world. I'm not talking about the white sandy beaches of Daytona Beach, Jacksonville Beach and St. Augustine Beach. The beaches around here are reddish, non swimming, beaches with rock outcropings. Some are mostly large rocks with little sand. It's on these same beaches that I found a 2 inch arrow head with a sweet vein of white quartz running through it......probably traded from the Georgia mountain area. There are abundant black fossils here as well....we've found.lots of turtle shell, camel teeth, vertabrae, one 3 inch vertabrae with a wonderful piece of hollow spinal cord intact, of course shark teeth and just over the dune line to the intracoastal waterway , we have found many pottery shards in the water's edge. The shards span anywhere from 8 to 10 thousand years in age and some even have fingerprints in them. Most of the shards are from the 8 thousand age range and are more refined than the older "orange period" pieces. These are from burial sites which were engulfed by the waterway over time. They are red clay and every piece is charred black on one side.......the concave side and this is probably due to the firing techneque of the time. Ok....now I'm off track again......sorry, will attach more photos of the fulgurites.
Thanks Guys,
Michael

If the beach where these were found is made up mostly of broken down shells, to the point of sand, wouldn't the fulgurite be mostly calcium carbonate as well?

Michael, all fulgurites I've seen have been formed predominantly from quartz sand, which partially melts to silica glass when struck by lightning. Calcium carbonate sand doesn't melt; there isn't any "calcium carbonate glass", so no fulgurites. Florida has a lot of fulgurites - more than any other U.S. state, but you'll have to go to a quartz sand area to find them. Good luck hunting!

Alfredo:

Almost all manufactured glass contains calcium carbonate. The main ingredients for glass are: silica sand, sodium carbonate and calcium carbonate.(Soda-lime-silica glass). The calcium carbonate does melt and forms glass in the presence of silicates.

All fulgurites are not made of quartz sand. There are rock fulgurites (made from any number of target material rocks), sand fulgurites of various composition, loess fulgurites and clay sand fulgurites. Ancient fulgurites can have lechatelierite centers with calcite cemented quartzose sand exteriors. There are probably other unrecognized categories of fulgurites as well,but it's a highly understudied area. There are no books on fulgurites! (Though I'm working on one).

Michael,

We have many massive fulgurites (fulguroids), that look very similar to yours. They are possibly 50 million years old, (the age of petrified wood found alongside them), and were found in the Arizona desert. I'll attach some pictures.
Most people are only familiar with the common tube fulgurites found on beaches and sand dunes worldwide. These can be days old, or around 15,000 years old, (Sahara Desert).

I don't understand how you could have found ancient fulgurites on the beach in Florida. I've only seen the recent tubular ones and have never seen any like yours from Florida, or anywhere else. Your giant fulguroid is the only one I've seen like ours, so they can't be too common.

You could try listing them on eBay, but no one will believe they're actually fulgurites. Even the Smithsonian didn't recognize yours as fulgurites.

Lightning does very strange things when it hits the ground, it's a very understudied area. I've attached some pics of some of the strange shapes of fulguroids that we've found.

Phil Whitmer

Fulgarites and Petrified wood are formed in extremely different circumstances.
If I parked a Model T next to a Hummer would you believe they came from the same place.
I would also begin to tell you how informed Alfredo is, but he can defend himself.
AK

I agree that carbonate and silica together are great ingredients for glass, but the glass is then primarily calcium silicate (with other components) and not calcium carbonate - the glass certainly isn't going to fizz if you drop acid on it. The question was whether a fulgurite could be composed of carbonate, and I doubt that, although there might be carbonate grains adhering to the exterior. I've yet to see any fulgurite that wasn't dominantly composed of silicates; if anyone has one, please show us. ;-))

I would hesitate to call any of tese structures fulgurites - it would be good to have them carefully examined mineralogically. I would suspect they are calcareous concretions.
Though I have seen some opaline structures in beach sand that were thought to be the result of fires. I guess if there is a lot of lime and salt you could get some interesting reactions on heating.

Ralph

Hi Michael,

It seems that your initial question of value and marketability has evolved into a question of it's correct identification.

Alfredo, posed the first logical question or request to you, asking if you would image a cross-section for others on the thread to observe and comment on, you did not provide this. Next, I asked if your specimen displayed any "hollow" features, your response was no. You also added, "I do know that not all fulgurites are hollow." (RED FLAG). Beyond these questions and remarks, nothing has transpired to progress the most important question ie, Are these actually fulgurites?

The only way this can be sorted out is by examination and analysis. Do all sand fulgurites have a hollow channel? The answer is most do. In formation the ground is heated to an average of approximately 2500 C. The core of this strike as it enters the ground may be much hotter. The hollow channel that is formed represents the area which was essentially vaporized. Beyond this "hollow channel" concentrically, "melting" is initiated, with temperatures of somewhere between 1400 and 1800 C (at least) required the melt the sand. Upon cooling, a glass is formed. Beyond this concentic zone of melting, the surrounding soils, sands, etc. may be partially melted and as a consequence and upon cooling will form a mixed assemblage with phases of glass and minerals, that will be otherwise "attached" or "cemented" for lack of a better word to the greater fulgurite structure. Also "branches" can and are often are produced during this process, all having a similar cross-sectional profile, all this happening in mere microseconds.

You asked, "If the beach where these were found is made up mostly of broken down shells, to the point of sand, wouldn't the fulgurite be mostly calcium carbonate as well?" The answer is no. Calcium carbonate would be reduced, the heat would drive off the carbon dioxide and you would be left with an oxide of calcium, CaO, which could be chemically measured in the the fulgurite glass but again NO carbonate would exist at all. Fulgurite glass generally will have between 90 and 99% SiO₂. Depending on the the initial composition of the groundmass other oxides, ie. Al₂O₃, Fe₂O₃, CaO, etc will exist as well.

Phil said, "Almost all manufactured glass contains calcium carbonate. The main ingredients for glass are: silica sand, sodium carbonate and calcium carbonate.(Soda-lime-silica glass). The calcium carbonate does melt and forms glass in the presence of silicates." This is not accurate. As I stated, when heated to temperatures necessary to form fulgurites, the CaCO₃ (calcium carbonate) is reduced, driving off CO₂ gas and producing CaO, calcium oxide, only typically a minor component in ANY glass.

Conclusions There is seldom a circumstance where you can postively ID a specimen as a fulgurite from an image, especially when NO cross-section is displayed. Michael should have a small portion of his specimen cut and polished, demonstrating a cross-section. This would give him an idea as to it's validity. If it then appears to be a fulgurite, it should be analyzed to determine if it is a "glass" rather than a mineral assemblage. Testing a small piece in muriatic acid could not hurt as well. If it is a calcium carbonate mineral assemblage, it will be highly reactive, fizz and completely dissolve. If it is a fulgurite it will not dissolve, with the only reactivity occuring as possible "attached" carbonates react. Additionally, I agree with Ralph concerning the specimens from "Joshua Tree".

Final Comments Phil, I think Joshua Tree Museum is wonderful with a great purpose, best of luck with it's future success. Michael, you really owe it to yourself to have this tested if you believe in it. Try contacting a the Geology Dept of a university in your area, most would be happy to help and you would be able to get the facts on it. Good luck Michael.

All the Best,
Ron Gyllenhammer



Edited 1 time(s). Last edit at 09/27/2009 03:35PM by Ronald John Gyllenhammer.

Hi Michael:

Interestingly here is a man made fulgurite from a downed power line that fell onto a pile of clam shells.

[www.google.com]

Wow that's a long url! You have to scroll down for the clam shell embedded fulgurite.

Phil Whitmer

Hi Adam;

First off, let me clearly state I am a museum curator/science writer, NOT a real scientist! I do however understand the basics of geology. If on a dig, I found a Hummer and a Model T in the same strata, I would consider this good evidence that they could be roughly the same age. I'll attach some pics of fulgurites firmly attached to pieces of pet wood of a known age. I know of no other examples of this phenomena. I am open to explanations as to how this happened if the formation of the fulgs and pet wood were not contemporaneous events. Really, I have no idea how this could have happened, I only have the fossil evidence that somehow an ancient fulgurite became attached to a piece of petrified wood.

Note: the third picture is the backside of the same piece of wood.

Phil Whitmer

Alfredo:

No one is questioning the fact that lechatelierite is composed primarily of SiO2. I think Ronald makes that perfectly clear.

Phil Whitmer

Looks like calcareous concretions to me as well.

Hi Ralph & Uwe:

These formations have been mineralogically examined by a leading fulgurite researcher, Matt Pasek at the University of Arizona. He determined the majority of them to be lightning formed fulgurites/fulguroids (the mineral assemblages spoken of by Ronald). He had doubts about some of them that he had not personally examined. Matt is a researcher mainly concerned with the meteoritic and fulguritic sources of phosphorus and their role in the origins of life on Earth. However, he knows an awful lot about fulgurites and is proposing a new classification system for them. Our museum donated many kilos of study material to Matt that he used in the writing of his latest paper: Lightning-Induced Reduction of Phosphorus Oxidation State, published July 13, 2009 in the journal Nature Geoscience. Our museum is credited in the Aknowledgements section at the end of the article. The article includes a photograph of a backscattered electron microprobe image of one of our fulgurites. (Figure 2b).

[www.lpl.arizona.edu]

Hi Ronald,

First off, do you mind if I quote you in the booklet/pamphlet (in progress) on fulgurites (hopefully to be expanded into a book) that I'm working on?
Any thoughts on the pet wood with attached fulgurite?

Are you familiar with the fulgurites found in Arizona, Nevada and Utah? The vast majority of them are not hollow, though most have gas escape holes in the ends. The exteriors are mainly calcite cemented grains of quartz sand.

Phil Whitmer

JTM,
This is a horse of a different color.
Fulgarites attached to, not just near pet wood.
Got me thinking, is it some type of fulgarite Psuedomorph?
Started as a typical fulgarite, then psuedomorphed, or a cast replacement?
The wood has been replaced/petrified, why not the contacting minerals?
That or calcareous concretions is my guess.

P.S. Im not really a scientist either, I just know petrified wood and fulgarites, are formed in extremely different processes.

Hi Phil,

There are many sources, I'm sure considered to be more authoritative, accurately descriptive and comprehensive than my quickly written statements. However, the words I used were my own and you may quote me should you find it of benefit to your non-profit and as long as I assume no liability for it's use.

You asked, "Any thoughts on the pet wood with attached fulgurite?" Assuming for the moment that your description and identification of both the apparent “fulgurite” and attached/adjacent “petrified wood” is correct, an explanation of the formation may be possible. However, there are many unknowns here. What was the geologic setting in which this was found? What was the surrounding material, soil, sand, rock? Was it found in a stream bed? Where it was found, was this the location of it's original formation? Who knows? I can speculate on any number of possibilities but at the end of the day, any of these hypotheses would simply be "WAGS" without answers to these questions. We can assume for a moment at least (as long as the attached "fulgurite" is a real fulgurite) the attached "fulgurite" would be classified as a sand fulgurite and not a rock fulgurite. This would likewise infer that when your attached "fulgurite" was formed, lightning struck either sand, soil or other sediments that had not undergone lithification. From there and onward, it's anyone's guess. The adjacent "petrified wood" protolith could have already completely oxidized, been replaced by sediments and not yet lithified OR it could have been silicated millions (or any number) of years ago and was and just deposited in the sediment bed, sand or soil as a remnant from a completely different area or geologic setting. MAYBE, maybe, maybe... Only God knows at this point.

In regard to your question, "Are you familiar with the fulgurites found in Arizona, Nevada and Utah? The vast majority of them are not hollow, though most have gas escape holes in the ends. The exteriors are mainly calcite cemented grains of quartz sand." Yes I am familiar with fulgurites from these areas.

One thing you should understand though you may, is that there are two general types of fulgurites; sand fulgurites and rock fulgurites. Sand fulgurites are very common, rock fulgurites are rare and most found were at higher altitudes when produced. Most if not ALL sand fulgurites are formed and found with hollow channels/tubes as described in my previous post. This is a universally known and excepted fact. Some of the sand fulgarites are open at both ends, some are not. Fulgurite length is finite. This because at one final point, the potential of the lightning strike is matched, the charge is sufficently grounded and the remaining heat generated beyond the generated fulgurite vaporization and melt path is insufficent to create a melt, terminating the fulgurites length. At this end there may or may not be an opening. At the same time you can be assured it is substantively hollow or has a hollow channel, again due to vaporization. "Gas escape holes" is probably not the best way to describe these hollow channels, since anything in the lightning path is completely vaporized and escape is provided at that instant. It should also be mentioned that during any rapid melt/cooling sequence there will likely be gas produced from chemical reactions that will not have sufficent time to escape the melt, forming vesicles of trapped gases. Rock fulgurites are produced when the lightning strike reacts with rock, lithified strata, sandstone, any rock material for that matter as far as I know. Here is where you are likely to find occasional shallow melts or even mere crusts without a hollow channel. The depth is shallow, the temperatures are likely higher, the physics of force are constrained to a smaller area and entire area produces a melt, so even though the hollow channel was probably produced, the melt was hotter, more intense and the channel filled partially or fully with the melt product. The smooth, non-channeled ones you displayed as images, if truly fulgurites, were likely formed in a silicaceous sandstone. Also, the calcite cementation of quartz grains you describe occurs as a result of the lithification of sediments in a geologic setting and has nothing to do with lightning. This is why cross-section observation and petrographic or other analysis to determine the presence of glass and mixed glass/mineral phases is important. We have all seen things that resemble fulgurites that end up being calcareous concretions as suggested by others, those who by the way, would certainly know if handed one.
Phil, I really blew the budget on time for this one. I hope my post was not to long and overpowering. You asked alot of questions and I wanted to answer them completely and to the best of my ability and personal understanding. Thanks for your contributions to the thread.

Ron