dreamrocks
fully equipped rock polisher
I got lucky this morning and was able to post this no others since
Member since November 2018
Posts: 1,232
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Post by dreamrocks on Oct 19, 2024 8:57:04 GMT -5
That stone kinda looks to dark for Pariaba. I have herd of Paraiba also referred to as pool water blue and more closely refers to the true color. I would definitely call it’s color closer to indicolite tourmaline then Paraiba. Because of the outer edges of the stone being very dark to almost blackish in color. That stone may not have been in costume jewelry at all. Then you also said you cleaned off the stone but has attracted a bunch of dust after? You also said you found none or saw no bubbles right? Was that using a jewelers loupe? You won’t know if there’s bubbles or not without a loupe. A 25 year plus piece of glass will definitely have bubbles in it. Now a days they come a long way to get rid of the bubbles. Glass is known for having bubbles in it depending on the stone that’s being imitated all have a signature. Bubbles form in either in a line or sometimes like a v pattern or in clusters, the bubbles range in size from large to very small both needing a good loupe to see them. However it’s not as typical for glass to attract lint or dust like tourmaline does. Another thing about tourmaline’s ability to become electromagnetic and collect dust particles of lint. Some blue tourmaline’s also has another ability to be attracted to a magnet. These are the simplest tests to do on a possible tourmaline without gem tools. Use a tissue and rub one end of stone for a couple of minutes 2-3 minutes may do it then a dryer sheet may have enough lint when rolled into a ball above the stone and the dust falling near the stone. I would use tweezers to hold the stone and move around the dust pile see if there’s any reaction as you get closer to the pile of dust. The dust should be attracted to the stone if it’s a tourmaline and charged enough. For the magnetic test you will need a very strong magnetic to test. varianceobjects.com/blogs/gemstone-history/tourmaline-mythology-the-electromagnetically-charged-gemstone www.gemstonemagnetism.com/magnetic_indexwww.gemstonemagnetism.com/tourmaline_black_blue_and_greenwww.gemstonemagnetism.com/tourmalines_pg_3   I doubt it’s a perfect bubble free chunk of glass being over 25 years old. |
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Post by rockjunquie on Oct 19, 2024 9:13:33 GMT -5
Thank you for that detailed response! I used to have all kinds of gem books because I collected gems. (I have since gotten rid of 99% of gems and all books.) You present some good ideas. I'll try the magnet first since I have some rare earth magnets. Thanks! I doubt it's tourmaline, but I'll give it a look see.
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wargrafix
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Post by wargrafix on Oct 19, 2024 9:52:09 GMT -5
Is it possible that natural helenite exists?
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dreamrocks
fully equipped rock polisher
I got lucky this morning and was able to post this no others since
Member since November 2018
Posts: 1,232
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Post by dreamrocks on Oct 19, 2024 10:05:38 GMT -5
This color is very close to Paraiba tourmaline but has just a touch to much green without the use of gem tools to see the green. It also has a few bubbles to prove it’s not tourmaline or aquamarine but to the ordinary customer not knowing the difference could be tricked into buying either fake name. This is glass    |
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Post by rockjunquie on Oct 19, 2024 10:54:42 GMT -5
Is it possible that natural helenite exists? I don't think so. |
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dreamrocks
fully equipped rock polisher
I got lucky this morning and was able to post this no others since
Member since November 2018
Posts: 1,232
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Post by dreamrocks on Oct 19, 2024 11:35:00 GMT -5
Thank you for that detailed response! I used to have all kinds of gem books because I collected gems. (I have since gotten rid of 99% of gems and all books.) You present some good ideas. I'll try the magnet first since I have some rare earth magnets. Thanks! I doubt it's tourmaline, but I'll give it a look see. Your welcome I did a quick search on synthetic gems and this is what I came up with. Both gem materials clearly state there’s bubbles in them as does glass. Glass is listed in another section Tell you what I would consider buying that stone for $10.00 to put your mind at ease. Or I would buy that stone and the hole bag of gems for $25.00.    The point is bubbles verses no bubbles whether synthetic or glass both have bubbles of some shape & size |
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jamesp
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Post by jamesp on Oct 19, 2024 12:56:27 GMT -5
Nope, no fancy kiln with gas or vacuum Rockoonz . You got me wondering if I should ask jamesp next time he has that urge to melt glass, if I could send it to him, to melt for me ? But then he doesn't have that fancy kiln either-so likely I'm on my own, with no one to blame the bubbles on, but myself  Patty
I did melt samples of a wide variety of obsidian Patty. Most of them basically 'foamed' and turned into what looks like pumice(or is pumice ?). Not pretty. Seemed like one sample blob melted well. Obsidian is about guaranteed impure compared to the precision blends of art/fusing glass. Guessing a gemologist could test that material in a jiff, perhaps an index of refraction test or others rockjunquie. All glass I ever melted was done just under 1500F. vegasjames seemed to know about the reaction of felspar... from google: Pumice is a type of volcanic rock, essentially made up of highly vesicular volcanic glass, formed when lava with a high gas content rapidly cools and depressurizes during a volcanic eruption, trapping gas bubbles within the solidifying rock, giving it its characteristic porous texture; it is primarily composed of silica-rich minerals like feldspar and quartz, making it a felsic igneous rock And then the chemistry of colored glass...:  |
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Post by rockjunquie on Oct 19, 2024 17:26:43 GMT -5
Thank you for that detailed response! I used to have all kinds of gem books because I collected gems. (I have since gotten rid of 99% of gems and all books.) You present some good ideas. I'll try the magnet first since I have some rare earth magnets. Thanks! I doubt it's tourmaline, but I'll give it a look see. Your welcome I did a quick search on synthetic gems and this is what I came up with. Both gem materials clearly state there’s bubbles in them as does glass. Glass is listed in another section Tell you what I would consider buying that stone for $10.00 to put your mind at ease. Or I would buy that stone and the hole bag of gems for $25.00. The point is bubbles verses no bubbles whether synthetic or glass both have bubbles of some shape & size I have some really strong rare earth magnets. No reaction at all. 
I think I have sold everything that came in that bag. I used to wrap a lot more gems. Some were very nice.
I'd be taking your 10 bucks and I'm no thief.  |
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Post by vegasjames on Oct 19, 2024 18:36:56 GMT -5
Is it possible that natural helenite exists? Not likely. The blast crated a pyroclastic flow, which would not be hot enough to melt the silica to liquid. Some pyroclastic flows can get hot enough though to fuse the sand and rock. |
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Post by vegasjames on Oct 19, 2024 18:41:13 GMT -5
Nope, no fancy kiln with gas or vacuum Rockoonz . You got me wondering if I should ask jamesp next time he has that urge to melt glass, if I could send it to him, to melt for me ? But then he doesn't have that fancy kiln either-so likely I'm on my own, with no one to blame the bubbles on, but myself Patty
I did melt samples of a wide variety of obsidian Patty. Most of them basically 'foamed' and turned into what looks like pumice(or is pumice ?). Not pretty. Seemed like one sample blob melted well. Obsidian is about guaranteed impure compared to the precision blends of art/fusing glass. Guessing a gemologist could test that material in a jiff, perhaps an index of refraction test or others rockjunquie . All glass I ever melted was done just under 1500F. vegasjames seemed to know about the reaction of felspar... from google: Pumice is a type of volcanic rock, essentially made up of highly vesicular volcanic glass, formed when lava with a high gas content rapidly cools and depressurizes during a volcanic eruption, trapping gas bubbles within the solidifying rock, giving it its characteristic porous texture; it is primarily composed of silica-rich minerals like feldspar and quartz, making it a felsic igneous rock And then the chemistry of colored glass...: Obsidian can also weather with water to form perlite. |
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jamesp
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Post by jamesp on Oct 20, 2024 7:53:01 GMT -5
I did melt samples of a wide variety of obsidian Patty. Most of them basically 'foamed' and turned into what looks like pumice(or is pumice ?). Not pretty. Seemed like one sample blob melted well. Obsidian is about guaranteed impure compared to the precision blends of art/fusing glass. Guessing a gemologist could test that material in a jiff, perhaps an index of refraction test or others rockjunquie . All glass I ever melted was done just under 1500F. vegasjames seemed to know about the reaction of felspar... from google: Pumice is a type of volcanic rock, essentially made up of highly vesicular volcanic glass, formed when lava with a high gas content rapidly cools and depressurizes during a volcanic eruption, trapping gas bubbles within the solidifying rock, giving it its characteristic porous texture; it is primarily composed of silica-rich minerals like feldspar and quartz, making it a felsic igneous rock And then the chemistry of colored glass...: Obsidian can also weather with water to form perlite. This must be a slow process James ? Guessing obsidian is most commonly containing iron which may assist in degradation but that is just a guess. Glass melts well with opal particles, silica particles almost always causes cracks, but this is likely due to different COE's. I have experienced various glass being harder or tougher after using a glass cutter repeatedly on many colors made by the same manufacturer. Some cut with little pressure on the glass cutter, some require higher pressure. Opaque glass is almost always softer(or less tough). |
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Post by vegasjames on Oct 20, 2024 8:48:49 GMT -5
Obsidian can also weather with water to form perlite. This must be a slow process James ? Guessing obsidian is most commonly containing iron which may assist in degradation but that is just a guess. Glass melts well with opal particles, silica particles almost always causes cracks, but this is likely due to different COE's. I have experienced various glass being harder or tougher after using a glass cutter repeatedly on many colors made by the same manufacturer. Some cut with little pressure on the glass cutter, some require higher pressure. Opaque glass is almost always softer(or less tough). Yes, it would be a slow process. And I agree the iron would play a role as glass is degraded by metal hydroxides. Dissociation of the water will form a negatively charged hydroxyl group that attaches to a positively charged metal forming the metal hydroxide.
Funny you should mention the opal with glass as we have a large opal field here in Nevada where the opal gets crushed to make glass.
I always wondered if glasses with different COEs could all be melted together to create a homogeneous mix to stabilize the glass?
The opaque glass being softer makes sense as many of the minerals used to opacify glass are very soft.
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jamesp
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Post by jamesp on Oct 20, 2024 11:38:22 GMT -5
This must be a slow process James ? Guessing obsidian is most commonly containing iron which may assist in degradation but that is just a guess. Glass melts well with opal particles, silica particles almost always causes cracks, but this is likely due to different COE's. I have experienced various glass being harder or tougher after using a glass cutter repeatedly on many colors made by the same manufacturer. Some cut with little pressure on the glass cutter, some require higher pressure. Opaque glass is almost always softer(or less tough). Yes, it would be a slow process. And I agree the iron would play a role as glass is degraded by metal hydroxides. Dissociation of the water will form a negatively charged hydroxyl group that attaches to a positively charged metal forming the metal hydroxide. Funny you should mention the opal with glass as we have a large opal field here in Nevada where the opal gets crushed to make glass. I always wondered if glasses with different COEs could all be melted together to create a homogeneous mix to stabilize the glass? The opaque glass being softer makes sense as many of the minerals used to opacify glass are very soft.
Sounds like opal is common there, nice to have such a resource. The finished glass product would be nice to see. Perhaps brown/mahogany obsidian is colored by iron, always wondered. Apparently obsidian can have a variety of metal fused into it. It is sort of a 'rogue' glass at times but can be pure glass too. Would make an interesting study. Maybe these chemicals are familiar to you James: "To make glass opaque, materials like opaque glass frit (powdered glass with added opacifiers) are typically fused into the glass during the manufacturing process, which essentially creates tiny particles within the glass that scatter light, preventing it from passing through completely. Key points about making glass opaque: Opacifiers: These are the key ingredient that makes glass opaque, and common examples include ceramic oxides like titanium dioxide (TiO2) or zirconium oxide (ZrO2)." May have heard that common(felspar rich) kaolin(rich in aluminum oxide)is used as an opacifier. "I always wondered if glasses with different COEs could all be melted together to create a homogeneous mix to stabilize the glass?". Perhaps if the were mixed well in the molten form or **mixed as a fine powder first. COE difference spell disaster when mixed in chunks. A glass blower performs one of the most accurate tests to compare COE between two different glasses - he melts the two side by side and by gravity a long thread say 18 inches long exudes from each chunk. Then he brings the molten threads together so they fuse together. If they stay straight as they cool they are of equal COE's, if they curve then the glass on the inside of the curve has a lower COE. **I believe the glass industry crushes and blends mixed COE glass first and then melts it. See Strategic Materials:  |
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Post by vegasjames on Oct 20, 2024 16:19:23 GMT -5
Yes, it would be a slow process. And I agree the iron would play a role as glass is degraded by metal hydroxides. Dissociation of the water will form a negatively charged hydroxyl group that attaches to a positively charged metal forming the metal hydroxide. Funny you should mention the opal with glass as we have a large opal field here in Nevada where the opal gets crushed to make glass. I always wondered if glasses with different COEs could all be melted together to create a homogeneous mix to stabilize the glass? The opaque glass being softer makes sense as many of the minerals used to opacify glass are very soft.
Sounds like opal is common there, nice to have such a resource. The finished glass product would be nice to see. Perhaps brown/mahogany obsidian is colored by iron, always wondered. Apparently obsidian can have a variety of metal fused into it. It is sort of a 'rogue' glass at times but can be pure glass too. Would make an interesting study. Maybe these chemicals are familiar to you James: "To make glass opaque, materials like opaque glass frit (powdered glass with added opacifiers) are typically fused into the glass during the manufacturing process, which essentially creates tiny particles within the glass that scatter light, preventing it from passing through completely. Key points about making glass opaque: Opacifiers: These are the key ingredient that makes glass opaque, and common examples include ceramic oxides like titanium dioxide (TiO2) or zirconium oxide (ZrO2)." May have heard that common(felspar rich) kaolin(rich in aluminum oxide)is used as an opacifier. "I always wondered if glasses with different COEs could all be melted together to create a homogeneous mix to stabilize the glass?". Perhaps if the were mixed well in the molten form or **mixed as a fine powder first. COE difference spell disaster when mixed in chunks. A glass blower performs one of the most accurate tests to compare COE between two different glasses - he melts the two side by side and by gravity a long thread say 18 inches long exudes from each chunk. Then he brings the molten threads together so they fuse together. If they stay straight as they cool they are of equal COE's, if they curve then the glass on the inside of the curve has a lower COE. **I believe the glass industry crushes and blends mixed COE glass first and then melts it. See Strategic Materials: Mahogany obsidian is colored by iron oxides such as magnetite and hematite.
Yes, I am familiar with those chemicals. We even have a type of titanium oxide out here I collect once in a while in the form of ilmenite, which is iron titanium oxide. There are various other opacifiers commonly used though. Most commonly tin oxides, but also barium carbonate, talc, arsenic oxide, tricalcium phosphate, bone ash, etc. What i used as an opacifier will depend on various factors such as desired stiffness of the glass, and also if you are using an electric or gas fired kiln as gas fired kilns can cause reductions of oxides and carbonates. A good source of info on the chemicals used in glasses, such a gazes is Digitalfire digitalfire.com/index.php
I am familiar with glass blowing. My brother did this for many years. Technically glass sculpting instead of blowing. He apprenticed under Kemp Curtis, who at the time was the second best glass sculpter in the country. I would go down and watch and do their sand blasting for them to frost the pieces. When bored I would go through Kemp's glass books reading up on glass formation and techniques.
Kaolin and bentonite clays are also common sources of silica and aluminum oxides for opal formation. The first common opals I produced, I used clean kitty litter, which was bentonite clay. Recently ordered 50 pounds of bentonite powder to run some new opal making experiments. Have a bunch of porcelain clay a well to experiment with.
Yes, would make sense the mixing of different COEs would work as when they recycle glass they do sort by colors, but they are not going to sort glasses by COEs.
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jamesp
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Post by jamesp on Oct 21, 2024 15:31:11 GMT -5
It's great to have an in house RTH chemist in vegasjames. |
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Post by vegasjames on Oct 21, 2024 15:40:30 GMT -5
It's great to have an in house RTH chemist in vegasjames . Did I ever post my homemade turquoise? Real easy to make. Takes a couple of weeks for the chemical reactions to complete forming a water insoluble hydrated copper aluminum phosphate. Right now the material is thin and brittle. Have an experiment I want to run to make it thicker and silicated. Trying to track down a chemical I need. |
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Post by vegasjames on Oct 21, 2024 22:02:40 GMT -5
This is my turquoise I made in my kitchen. The solution  The turquoise once the chemical reaction finishes. Next experiment is to try to make the turquoise thicker and more stable by silicifying the turquoise. Right now it can only really be used for inlay.  |
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realrockhound
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Post by realrockhound on Oct 21, 2024 22:33:02 GMT -5
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whalecottagedesigns
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Post by whalecottagedesigns on Oct 22, 2024 2:21:59 GMT -5
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wargrafix
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Post by wargrafix on Oct 23, 2024 7:25:37 GMT -5
This is my turquoise I made in my kitchen. The solution The turquoise once the chemical reaction finishes. Next experiment is to try to make the turquoise thicker and more stable by silicifying the turquoise. Right now it can only really be used for inlay. *Breaking Bad theme plays* |
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