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Gypsum?
Mar 27, 2023 8:31:58 GMT -5
Post by vegasjames on Mar 27, 2023 8:31:58 GMT -5
Here's an unprocessed piece which shows a thin layer of the black opal that is characteristic of my sites in NM. It can be thick or thin, located in cracks or solid masses but still in form of the wood it is replacing. As I understand it, opal is a silica product on its way to being chalcedony so, its possible that all the pretty pet wood you have seen went through this stage in its ultimate formation. That is very interesting! I have been trying to research and understand what opal is lately. I have quite a few petrified woods that are covered with black material. Some of them seem to be that way all the way through while others have the beautiful wood grain and colors underneath the black. I’ve been wondering what the black covering is, I was assuming it was some kind of slate type product or something. I will do a search on opal here on the site today and try to figure out more about it. Many thanks man! Could also be opal. I have various pieces of opalized wood, some with black in it. I will post a few examples of some of my opalized wood in a minute.
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Post by vegasjames on Mar 27, 2023 8:39:05 GMT -5
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Post by vegasjames on Mar 27, 2023 8:42:26 GMT -5
My write up on opal:
General Facts About Opal
-There are around 300 types of opal separated in to two primary categories. Precious and common. Precious opal is any opal with a play or color (flash) as where common opal is any opal without a play of color.
-Precious opal consists of smaller silica spheres in an ordered arrangement. The size of the spheres determines the colors in the flash. Common opal consists of varying sizes of silica spheres in a disordered arrangement.
-Opal is generally considered amorphous, which means lacking crystalline structure. Although opal can contain crystalline compounds known as cristobalite and tridymite. If the opal contains only cristobalite then the opal is referred to as Opal-C. If the opal contains both cristobalite and tridymite then the opal is referred to as Opal-CT. Completely amorphous opals are referred to as Opal-AG (amorphous gel) such as precious opal and Opal-AN (amorphous network) such as hyalite opal.
-The general chemical composition of opal is amorphous silicon dioxide (silica) although opal can also contain varying amounts of aluminum oxide as well as trace amounts of elements and other compounds. The aluminum oxide comes from the clay most opal forms from. The higher the aluminum oxide content and lower the water content the harder and more stable the opal is.
-Opal is also found on the tips of bee stingers, the sharp points of the stinging nettle plant and in diatoms, radiolarites and sea sponges.. Opal can also form from the silica rich bamboo sap and is referred to as “vegetable opal”.
-Contrary to popular geological teachings opal does not take millions of years to form. It has been shown that opal can form in very short periods of time, less than one year.
-Opal starts as a silica gel. The silica molecules naturally attract towards each other squeezing out water in the process. When sufficient water is squeezed out opal is produced. If all the water in the opal is lost then the opal converts in to a chalcedony including jasper or agate, or can convert in to chert/flint. The form of chalcedony formed depends in part on the silica source. Common chalcedony, jaspers and agates form from opal generated by inorganic silica sources. Chert/flint form from opal derived from biogenic silica sources.
-Because chalcedonies can form from opal, you can also find examples of opal mixed with chalcedonies as part of the opal has transitioned.
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Post by vegasjames on Mar 27, 2023 8:46:39 GMT -5
A post on opal formation I had done on another board:
Yes, I know jaspers and agates are form of chalcedony as is chert/flint, which are all forms of quartz. I have written on this a number of times. But jasper, agate and chert/flint just don't suddenly form. As I said, they are formed from opal. Opal starts as a silica gel. As the molecules move closer together water is squeezed out and the gel forms in to a solid. When a certain amount of water is left (3-21%) the result is opal. When less than 3% water is left as part of the structure the opal converts in to a chalcedony. The difference between the formation of common chalcedony, jasper and agate vs chert/flint is the silica source. The silica that forms common chalcedony, jasper and agate is usually sandstone or clays as where chert/flint is formed from opal produced from biogenic silica sources and is sedimentary. Opals also vary in hardness and stability. This is in part due to water content, but also due to the silica source. In the case of clays and diatomaceous earth the opals also pick up aluminum oxide from these sources increasing the hardness and stability of the opal. Another main difference between opal and chalcedonies is that opal is generally amorphous (lacking crystalline structure) as where chalcedonies are cryptocrystalline (microcrystalline). Quartz crystals are macrocrystalline. Addressing your comment of "Quartz and opal are silicate based and form, generally, as deposits left from water evaporation", that is not really true. Quartz crystals are formed hydrothermally. Without going in to a long explanation the simple explanation is that the silica is dissolved in water under extreme temperatures and pressures allowing the water to become supersaturated. As the solution cools the supersaturation is no longer stable and the silica starts to crystallize out of the solution. Therefore, not from evaporation. As for opal, it also forms in solution, and therefore not from evaporation. As mentioned, the silica polymerizes first in to a gel still within a solution and the molecules move closer together through electrostatic forces within the solution. Again, I am not going to go in to a long explanation, but opal does not really form from directly as silicon dioxide. Instead, the pH levels involved form silicic acids that can polymerize as opal gel then in to opal. So, the evaporation of silica hypothesis makes absolutely no sense. I have been playing with making opal for years. It is pretty simple process, and again is all done in solution, not through evaporation. In fact, as an experiment I tried simply evaporating ultra-fine crushed opal in water to see if the dissolved silica in the water would form opal. The answer is no. Again, there are other factors needed to convert the silica in to opal including changes in pH. The difference between precious and common opals involves silica sphere size and arrangement. The opalization of things like shells is also a little more involved. Silica has a high affinity for calcium, which is why organic opalized items are generally calcium rich such as shells and bones. Chalcedony does not replace the organics as you claim. Instead, the item such as wood is first opalized. Then as the opal loses more water the opalized wood turns to a chalcedony-based wood such as agatized or jasperized wood. Therefore, chalcedony-based wood is much older than opalized wood. Wood can also be replaced with pyrite when there is a high concentration of hydrogen sulfide present during the decay process. I have some samples of that as well.
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Post by Peruano on Mar 27, 2023 10:21:26 GMT -5
Its correct to say that many kinds of opal exist and it can occur in many different situations. I've always been amazed at the large seemingly pure opal "woods" that you post from Nevada. I call the material that I collect opalized wood, but in fact it is a fibrous wood derivative (like that posted by velodromed. It can be loose fibers especially on the surface, relatvely compact and solid a bit deeper in the specimen; the latter can show typical wood cell patterns and growth rings, and often will show pure black inclusions which in fact is the most obviously opal component. The black opal does not show growth rings. Based on where and how it occurs it appears to have invaded spaces (under bark, in cracks, hollow cavities, etc.) It will be very interesting to see if velodromed finds such black pure opal, or relatively compact opal like material that is a wood replacement. I guess what I'm saying is the the black seems to be opal "in wood", whereas the grey compact material may be "opalized" wood. what the chemical or geological makeup of the grey fibrous layer is may still be debatable. Clearly much of the beautiful Nevada wood posted in this thread is opalized wood showing grow rings etc evidencing replacement of wood by the opal. Here is what appears to be a root with the fibrous grey layer on the outside and a solid black opal interior (with no evidence of growth rings or cell structure of any kind). and yet another photo of examples of patterns seen when you subject them to a saw. Its all a bit fascinating.
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Post by velodromed on Mar 27, 2023 15:12:09 GMT -5
A post on opal formation I had done on another board: Yes, I know jaspers and agates are form of chalcedony as is chert/flint, which are all forms of quartz. I have written on this a number of times. But jasper, agate and chert/flint just don't suddenly form. As I said, they are formed from opal. Opal starts as a silica gel. As the molecules move closer together water is squeezed out and the gel forms in to a solid. When a certain amount of water is left (3-21%) the result is opal. When less than 3% water is left as part of the structure the opal converts in to a chalcedony. The difference between the formation of common chalcedony, jasper and agate vs chert/flint is the silica source. The silica that forms common chalcedony, jasper and agate is usually sandstone or clays as where chert/flint is formed from opal produced from biogenic silica sources and is sedimentary. Opals also vary in hardness and stability. This is in part due to water content, but also due to the silica source. In the case of clays and diatomaceous earth the opals also pick up aluminum oxide from these sources increasing the hardness and stability of the opal. Another main difference between opal and chalcedonies is that opal is generally amorphous (lacking crystalline structure) as where chalcedonies are cryptocrystalline (microcrystalline). Quartz crystals are macrocrystalline. Addressing your comment of "Quartz and opal are silicate based and form, generally, as deposits left from water evaporation", that is not really true. Quartz crystals are formed hydrothermally. Without going in to a long explanation the simple explanation is that the silica is dissolved in water under extreme temperatures and pressures allowing the water to become supersaturated. As the solution cools the supersaturation is no longer stable and the silica starts to crystallize out of the solution. Therefore, not from evaporation. As for opal, it also forms in solution, and therefore not from evaporation. As mentioned, the silica polymerizes first in to a gel still within a solution and the molecules move closer together through electrostatic forces within the solution. Again, I am not going to go in to a long explanation, but opal does not really form from directly as silicon dioxide. Instead, the pH levels involved form silicic acids that can polymerize as opal gel then in to opal. So, the evaporation of silica hypothesis makes absolutely no sense. I have been playing with making opal for years. It is pretty simple process, and again is all done in solution, not through evaporation. In fact, as an experiment I tried simply evaporating ultra-fine crushed opal in water to see if the dissolved silica in the water would form opal. The answer is no. Again, there are other factors needed to convert the silica in to opal including changes in pH. The difference between precious and common opals involves silica sphere size and arrangement. The opalization of things like shells is also a little more involved. Silica has a high affinity for calcium, which is why organic opalized items are generally calcium rich such as shells and bones. Chalcedony does not replace the organics as you claim. Instead, the item such as wood is first opalized. Then as the opal loses more water the opalized wood turns to a chalcedony-based wood such as agatized or jasperized wood. Therefore, chalcedony-based wood is much older than opalized wood. Wood can also be replaced with pyrite when there is a high concentration of hydrogen sulfide present during the decay process. I have some samples of that as well. Thank you for going above and beyond and exclamation. I am feeling good right now because I understood far more of what you were talking about and I would’ve just a few months ago. I’m still gonna have to Google a few things and cross reference to pull it all together, but you’ve strengthened my foundation of the knowledge. The woods that you are found are amazing. I have found a lot of petrified wood, but not as colorful and gorgeous as your pieces. You may have mentioned it, but I forget. What area did you find the petrified woods? All of mine are from Texas. Again, thank you for taking the time. I appreciate this very much.
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Post by velodromed on Mar 27, 2023 15:19:03 GMT -5
A post on opal formation I had done on another board: Yes, I know jaspers and agates are form of chalcedony as is chert/flint, which are all forms of quartz. I have written on this a number of times. But jasper, agate and chert/flint just don't suddenly form. As I said, they are formed from opal. Opal starts as a silica gel. As the molecules move closer together water is squeezed out and the gel forms in to a solid. When a certain amount of water is left (3-21%) the result is opal. When less than 3% water is left as part of the structure the opal converts in to a chalcedony. The difference between the formation of common chalcedony, jasper and agate vs chert/flint is the silica source. The silica that forms common chalcedony, jasper and agate is usually sandstone or clays as where chert/flint is formed from opal produced from biogenic silica sources and is sedimentary. Opals also vary in hardness and stability. This is in part due to water content, but also due to the silica source. In the case of clays and diatomaceous earth the opals also pick up aluminum oxide from these sources increasing the hardness and stability of the opal. Another main difference between opal and chalcedonies is that opal is generally amorphous (lacking crystalline structure) as where chalcedonies are cryptocrystalline (microcrystalline). Quartz crystals are macrocrystalline. Addressing your comment of "Quartz and opal are silicate based and form, generally, as deposits left from water evaporation", that is not really true. Quartz crystals are formed hydrothermally. Without going in to a long explanation the simple explanation is that the silica is dissolved in water under extreme temperatures and pressures allowing the water to become supersaturated. As the solution cools the supersaturation is no longer stable and the silica starts to crystallize out of the solution. Therefore, not from evaporation. As for opal, it also forms in solution, and therefore not from evaporation. As mentioned, the silica polymerizes first in to a gel still within a solution and the molecules move closer together through electrostatic forces within the solution. Again, I am not going to go in to a long explanation, but opal does not really form from directly as silicon dioxide. Instead, the pH levels involved form silicic acids that can polymerize as opal gel then in to opal. So, the evaporation of silica hypothesis makes absolutely no sense. I have been playing with making opal for years. It is pretty simple process, and again is all done in solution, not through evaporation. In fact, as an experiment I tried simply evaporating ultra-fine crushed opal in water to see if the dissolved silica in the water would form opal. The answer is no. Again, there are other factors needed to convert the silica in to opal including changes in pH. The difference between precious and common opals involves silica sphere size and arrangement. The opalization of things like shells is also a little more involved. Silica has a high affinity for calcium, which is why organic opalized items are generally calcium rich such as shells and bones. Chalcedony does not replace the organics as you claim. Instead, the item such as wood is first opalized. Then as the opal loses more water the opalized wood turns to a chalcedony-based wood such as agatized or jasperized wood. Therefore, chalcedony-based wood is much older than opalized wood. Wood can also be replaced with pyrite when there is a high concentration of hydrogen sulfide present during the decay process. I have some samples of that as well. Those fiber line pieces of black, opal, petrified wood, or a very intriguing. That white fibrous stuff is, or at least appears to be, exactly like what I found. I’m going have to cut mine in half just to look at its make up little bit closer. I have a feeling it’ll be the white fibrous stuff all the way through because it is so incredibly light. It’ll be interesting to find out though. Really appreciate everyone. Who comments on my questions. I tried a fossil forum and an another forum that had sub categories for gemstones and fossils… but my beginner questions were slightly ridiculed. Which is fine, I have thick skin, just meant that wasn’t the place for me. So I appreciate everyone’s time, and the information shared very much.
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Post by velodromed on Mar 27, 2023 15:19:59 GMT -5
Its correct to say that many kinds of opal exist and it can occur in many different situations. I've always been amazed at the large seemingly pure opal "woods" that you post from Nevada. I call the material that I collect opalized wood, but in fact it is a fibrous wood derivative (like that posted by velodromed. It can be loose fibers especially on the surface, relatvely compact and solid a bit deeper in the specimen; the latter can show typical wood cell patterns and growth rings, and often will show pure black inclusions which in fact is the most obviously opal component. The black opal does not show growth rings. Based on where and how it occurs it appears to have invaded spaces (under bark, in cracks, hollow cavities, etc.) It will be very interesting to see if velodromed finds such black pure opal, or relatively compact opal like material that is a wood replacement. I guess what I'm saying is the the black seems to be opal "in wood", whereas the grey compact material may be "opalized" wood. what the chemical or geological makeup of the grey fibrous layer is may still be debatable. Clearly much of the beautiful Nevada wood posted in this thread is opalized wood showing grow rings etc evidencing replacement of wood by the opal. Here is what appears to be a root with the fibrous grey layer on the outside and a solid black opal interior (with no evidence of growth rings or cell structure of any kind). and yet another photo of examples of patterns seen when you subject them to a saw. It’s all a bit fascinating. Out of sheer curiosity, where are your pieces from that are pictured here?
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Post by Peruano on Mar 27, 2023 15:24:45 GMT -5
Valencia County new mexico but I've seen similar material from Nevada.
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Post by velodromed on Mar 27, 2023 15:49:03 GMT -5
When we were rock hunting on the Llano river here in south-central Texas we found quite a few pieces of what looked like black/dark grey petrified wood, but it broke in half relatively easy and was dark all the way through, like below, with streaks of browns through it. Some of the pieces are considerably harder and I’m pretty sure when I tumble them the petrified wood I’m used to seeing will be underneath. Are these the opalized wood in process of turning perhaps? Maybe the process was stopped when it was uprooted or something? I thought it was slate that simply wore down until it looked similar to Wood. That is until I started finding the pieces that were much heavier and ‘tinked’ when hit together, [img alt=" " like hard rocks do.
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Post by vegasjames on Mar 27, 2023 18:30:37 GMT -5
Its correct to say that many kinds of opal exist and it can occur in many different situations. I've always been amazed at the large seemingly pure opal "woods" that you post from Nevada. I call the material that I collect opalized wood, but in fact it is a fibrous wood derivative (like that posted by velodromed. It can be loose fibers especially on the surface, relatvely compact and solid a bit deeper in the specimen; the latter can show typical wood cell patterns and growth rings, and often will show pure black inclusions which in fact is the most obviously opal component. The black opal does not show growth rings. Based on where and how it occurs it appears to have invaded spaces (under bark, in cracks, hollow cavities, etc.) It will be very interesting to see if velodromed finds such black pure opal, or relatively compact opal like material that is a wood replacement. I guess what I'm saying is the the black seems to be opal "in wood", whereas the grey compact material may be "opalized" wood. what the chemical or geological makeup of the grey fibrous layer is may still be debatable. Clearly much of the beautiful Nevada wood posted in this thread is opalized wood showing grow rings etc evidencing replacement of wood by the opal. Here is what appears to be a root with the fibrous grey layer on the outside and a solid black opal interior (with no evidence of growth rings or cell structure of any kind). and yet another photo of examples of patterns seen when you subject them to a saw. Its all a bit fascinating. The outer layer could still some form of calcium. Not all forms of calcium react to acids or react readily to acids. For example, dolomite, which is a calcium-magnesium carbonate only reacts to hydrochloric acid if finely powdered. The other possibility is that that it is a silica coating. Here in Nevada for example, a lot of our chalcedony has a hard, opaque and often white coating of silica. It has no visible crystal structure to the naked eye, but does not seen to be amorphous either. Have not done much testing on it, just know in this case it is hard to remove from the rocks. Been trying all sorts of things physically and chemically to remove it without damaging the specimens without any luck so far.
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Post by vegasjames on Mar 27, 2023 18:48:17 GMT -5
A post on opal formation I had done on another board: Yes, I know jaspers and agates are form of chalcedony as is chert/flint, which are all forms of quartz. I have written on this a number of times. But jasper, agate and chert/flint just don't suddenly form. As I said, they are formed from opal. Opal starts as a silica gel. As the molecules move closer together water is squeezed out and the gel forms in to a solid. When a certain amount of water is left (3-21%) the result is opal. When less than 3% water is left as part of the structure the opal converts in to a chalcedony. The difference between the formation of common chalcedony, jasper and agate vs chert/flint is the silica source. The silica that forms common chalcedony, jasper and agate is usually sandstone or clays as where chert/flint is formed from opal produced from biogenic silica sources and is sedimentary. Opals also vary in hardness and stability. This is in part due to water content, but also due to the silica source. In the case of clays and diatomaceous earth the opals also pick up aluminum oxide from these sources increasing the hardness and stability of the opal. Another main difference between opal and chalcedonies is that opal is generally amorphous (lacking crystalline structure) as where chalcedonies are cryptocrystalline (microcrystalline). Quartz crystals are macrocrystalline. Addressing your comment of "Quartz and opal are silicate based and form, generally, as deposits left from water evaporation", that is not really true. Quartz crystals are formed hydrothermally. Without going in to a long explanation the simple explanation is that the silica is dissolved in water under extreme temperatures and pressures allowing the water to become supersaturated. As the solution cools the supersaturation is no longer stable and the silica starts to crystallize out of the solution. Therefore, not from evaporation. As for opal, it also forms in solution, and therefore not from evaporation. As mentioned, the silica polymerizes first in to a gel still within a solution and the molecules move closer together through electrostatic forces within the solution. Again, I am not going to go in to a long explanation, but opal does not really form from directly as silicon dioxide. Instead, the pH levels involved form silicic acids that can polymerize as opal gel then in to opal. So, the evaporation of silica hypothesis makes absolutely no sense. I have been playing with making opal for years. It is pretty simple process, and again is all done in solution, not through evaporation. In fact, as an experiment I tried simply evaporating ultra-fine crushed opal in water to see if the dissolved silica in the water would form opal. The answer is no. Again, there are other factors needed to convert the silica in to opal including changes in pH. The difference between precious and common opals involves silica sphere size and arrangement. The opalization of things like shells is also a little more involved. Silica has a high affinity for calcium, which is why organic opalized items are generally calcium rich such as shells and bones. Chalcedony does not replace the organics as you claim. Instead, the item such as wood is first opalized. Then as the opal loses more water the opalized wood turns to a chalcedony-based wood such as agatized or jasperized wood. Therefore, chalcedony-based wood is much older than opalized wood. Wood can also be replaced with pyrite when there is a high concentration of hydrogen sulfide present during the decay process. I have some samples of that as well. Thank you for going above and beyond and exclamation. I am feeling good right now because I understood far more of what you were talking about and I would’ve just a few months ago. I’m still gonna have to Google a few things and cross reference to pull it all together, but you’ve strengthened my foundation of the knowledge. The woods that you are found are amazing. I have found a lot of petrified wood, but not as colorful and gorgeous as your pieces. You may have mentioned it, but I forget. What area did you find the petrified woods? All of mine are from Texas. Again, thank you for taking the time. I appreciate this very much. Opal in general is found all over Nevada. I have even found it here by Las Vegas, technically in Henderson, as well as one piece out by Goodsprings about 40 miles Southwest of here and by Searchlight about 40 mile South of Las Vegas. Most the opal though is going North. Lots of common opal in the Goldfield District about 3 hours North of here, which is where I also found 3 deposits of opalized wood and one back agatized log. There is hyalite opal slightly further North by Coaldale Junction. Then I have found some opal couple hours South of Reno in a uranium deposit. And there is all sorts of precious and common opal further North in Nevada, which is where the rest of the opalized wood in my pics came from, including around Reno, and up by the Nevada-Idaho border.
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Post by vegasjames on Mar 27, 2023 19:02:30 GMT -5
These look more like a schist. Phyllite and schist that it forms in to can look a lot like petrified wood. I will post some examples.
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Post by vegasjames on Mar 27, 2023 19:22:22 GMT -5
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Post by Peruano on Mar 28, 2023 7:21:17 GMT -5
The material from the Llano river doesn't look as much like wood; it seems to have a sedimentary/metamorphic layered look and not the fibrous texture that I "thought" I saw in your initial photos. Is it the same material as you included in your first posted photos?
I'm trying to dredge my mind for a layered volcanic with a low specific gravity as a possible candiate for the llano river stuff . . . but then I'd need an igneous source wouldn't I.
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Post by velodromed on Mar 28, 2023 12:06:01 GMT -5
These look more like a schist. Phyllite and schist that it forms in to can look a lot like petrified wood. I will post some examples. Ok cool, thanks! Something new to research with my wife.Thing is, some are much heavier and more solid than the other ones. Like there’s much more developed rock underneath the black surface. I decided to put a couple of small pieces in the vibe to see what happens lol. One that’s black all the way through and another that’s more ‘solid’, like I mentioned above. I’m probably not explaining it very well (I’m sick and wobbly but still tumbling).
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Post by velodromed on Mar 28, 2023 12:11:56 GMT -5
Man, that Phyllite looks interesting but not familiar. I don’t think we’ve run across any of it that I know of. We decided to take the mystery piece and cut it on the saw when I’m feeling better. I went and grabbed it and looked at it with my wife earlier. The first thing I realized is it’s not light weight, as I thought for some reason. It’s actually similar in weight to an equal size piece of petrified wood. Not sure why I thought it was light. Must’ve been the color lol. Again, many thanks. I appreciate all of your input.
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Gypsum?
Mar 28, 2023 14:04:33 GMT -5
Post by velodromed on Mar 28, 2023 14:04:33 GMT -5
The material from the Llano river doesn't look as much like wood; it seems to have a sedimentary/metamorphic layered look and not the fibrous texture that I "thought" I saw in your initial photos. Is it the same material as you included in your first posted photos? I'm trying to dredge my mind for a layered volcanic with a low specific gravity as a possible candiate for the llano river stuff . . . but then I'd need an igneous source wouldn't I. Up a couple of posts from here are pics of some of the black rock type stuff we found. I don’t think I posted those earlier at all. I thought it was all some type of slate, weathered down to look a bit like wood. But some of the pieces are more dense and ‘ting’ when tapped on another rock. I threw a small piece of each type in the vibe with 120 grit to see what happens.
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Post by velodromed on Mar 28, 2023 14:07:27 GMT -5
My wife found this rock in the Llano river and is wondering what it is. I initially thought chert…but now I’m not sure. Y’all have any ideas?
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Post by vegasjames on Mar 28, 2023 22:29:14 GMT -5
Man, that Phyllite looks interesting but not familiar. I don’t think we’ve run across any of it that I know of. We decided to take the mystery piece and cut it on the saw when I’m feeling better. I went and grabbed it and looked at it with my wife earlier. The first thing I realized is it’s not light weight, as I thought for some reason. It’s actually similar in weight to an equal size piece of petrified wood. Not sure why I thought it was light. Must’ve been the color lol. Again, many thanks. I appreciate all of your input. Phyllite is the precursor so schist. I is composed of tightly packed mica flakes with a much finer grain than schist. In person it is very metallic looking and is usually silvery. Although, I have also found it in green, and in gold colors.
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