Exploration of the Hollowed Galenas
Last Updated: 16th May 2011By Jessica Simonoff
I first saw the hollow Bulgarian galenas at the Springfield Mineral Show in 2009 and I was not initially suspicious. Shortly thereafter, I read the Mindat forum thread about these “reverse-skeletal Madan galenas” ( http://www.mindat.org/forum.php?read,55,157736,page=1 ). The posts to the topic made me curious and I wanted to explore the subject further. At the Houston Mineral Show, I was talking to Edward Rosenzweig of Edwards Minerals ( http://www.edwardsminerals.com ) about these galenas and the long discussion on Mindat. He said that he had several he had purchased in hopes of selling them, but stopped when he learned that they might not be natural. He also mentioned that he didn’t know what to do with them while the issue was still unresolved.
I said that I would be willing to try to get some that are known to be manmade and do some experiments, comparing the manmade pieces with the ones from Edward’s stock in hopes of being able to observe something which might lead to a conclusion. Edward agreed and loaned me two pieces for the experiment. Another person kindly gave me two pieces that had been made through microabrasion.
In this article, I will share my observations and pictures of the four pieces. First, here are some general observations I have with respect to all of the pieces:
- I exposed these pieces to shortwave UV light in hopes of being able to spot any glue that might be present. There was no fluorescence.
- I examined them with a hand lens and under my microscope in search of glue and found none. The primary observation is the stepped lines that occur in all 4 specimens.
- None of the crystals -natural or man-made- have a hole in the face that attaches to the matrix, yet all other faces seem hollowed out.
- On the man-made pieces, the faces of the crystals that would be hard to get to with a microabrasion tool are not hollow. On the pieces we got from Edward, faces of the crystals which are attached to another crystal or would be similarly hard to reach are not hollow either.
I will start with photos of one of the pieces that is not known to be man-made. Here is a picture of the whole piece:
The largest hollow galena crystal on this piece has a small (3 x 1.5 mm) quartz crystal inside it. Originally, we thought it was calcite, but three different acid tests using HCl showed no reaction. However, there is chlorite inside the crystal - this time we are almost sure of the identification. I have no evidence that the crystal is or is not glued to the specimen, but soaking the specimen in acetone overnight did not affect it. Here are some photos:
I looked closer at the quartz crystal under the microscope, and noticed this. The first photo shows the whole crystal. The second is a close up, and the last is an extreme close-up. There are specks of galena on the quartz, but not crystals. As far as I can see with the microscope, there are none of these specks included in the quartz.
I also took some close-up photos on the end of the quartz crystal which attaches to the matrix. It looks like it is damaged at the end that attaches to the galena but not the other one.
Another interesting feature of this piece are lines on the surfaces of the galena crystals. The lines tend to be roughly parallel but curve. Photos:
Now I will show some photos of the other piece that is not known to be man-made. It is different because instead of having hollow cubes, the galena's shape is more like a loop. Here are some photos of the whole piece:
I also took some close-up photos. The photo on the left shows shows a small quartz crystal growing out of the inside of the galena "loop" and the one on the right shows that there is some galena in or on a quartz crystal. This piece does not show the curved pattern of lines in the same way as the other piece. These line appear more random in their path. Another observation about this specimen is that the galenas have small shiny spots in seemingly random places.
Both of the galenas I have that are known to be man-made were created through microabrasion. Here is a full photo of the first one:
I also took a close-up of the inner bottom surface of the piece. Interestingly, the microabraded surfaces of the galenas displays a pattern of curved, parallel lines extremely similar to those shown on the first galena we received from Edward Rosenzweig:
Here are some photos of the other galena I have which is known to be man-made.
A full view photo:
I also took some close up photos. These show that this galena, which was created with microabrasion, also has the pattern of curved lines that the other two pieces show. But the lines are not as well defined as in the other pieces.
Lance Kearns offered to examine these specimens with the SEM at James Madison University. He let me stay in the SEM room while he was looking at them so I could see the images also. Because of a time limit, I selected three specimens to examine: one that was definitely man-made and two unknowns.
I looked at the man-made one first so that I could see what to look for in the other two. It had spherical indentations in the surface:
We looked a little more at the same sample and noticed a glass sphere, which was left-over abrasive material. That wasn't really a discovery because we always knew that piece was man-made, but it did help show us what to look for!
The next specimen was one of the unknowns (A)
Soon we noticed a glass sphere partially embedded in the surface of the galena, with craters and cracks around it.
Last, we looked at another unknown (B)
Like the other two, this one had craters in the surface:
There were also aluminum silicate crystals. We used the computer in the same room as the SEM to research and learned that aluminum silicate is widely used as an abrasive. The cracks coming from behind the aluminum silicate crystals (especially obvious on the third crystal from the left) are also evidence that the crystals are left over abrasive material.
This is also published in Mineral News magazine December 2010.
Because of the time limit we were not able to look at more than 2 unknown pieces, and the fact that these 2 were fakes DOES NOT mean that all similar pieces are!! The only test that was able to tell the difference was the SEM and without a much larger sample size it is unfair to draw any conclusion about all hollow galenas - only about the 2 that were tested.
It might be easiest if discussion about this article continue to occur in the following thread http://www.mindat.org/forum.php?read,55,157736,page=1 rather than in this article, where the posts may become unmanageable.
I said that I would be willing to try to get some that are known to be manmade and do some experiments, comparing the manmade pieces with the ones from Edward’s stock in hopes of being able to observe something which might lead to a conclusion. Edward agreed and loaned me two pieces for the experiment. Another person kindly gave me two pieces that had been made through microabrasion.
In this article, I will share my observations and pictures of the four pieces. First, here are some general observations I have with respect to all of the pieces:
- I exposed these pieces to shortwave UV light in hopes of being able to spot any glue that might be present. There was no fluorescence.
- I examined them with a hand lens and under my microscope in search of glue and found none. The primary observation is the stepped lines that occur in all 4 specimens.
- None of the crystals -natural or man-made- have a hole in the face that attaches to the matrix, yet all other faces seem hollowed out.
- On the man-made pieces, the faces of the crystals that would be hard to get to with a microabrasion tool are not hollow. On the pieces we got from Edward, faces of the crystals which are attached to another crystal or would be similarly hard to reach are not hollow either.
One of the galenas not known to be fake
I will start with photos of one of the pieces that is not known to be man-made. Here is a picture of the whole piece:
The largest hollow galena crystal on this piece has a small (3 x 1.5 mm) quartz crystal inside it. Originally, we thought it was calcite, but three different acid tests using HCl showed no reaction. However, there is chlorite inside the crystal - this time we are almost sure of the identification. I have no evidence that the crystal is or is not glued to the specimen, but soaking the specimen in acetone overnight did not affect it. Here are some photos:
I looked closer at the quartz crystal under the microscope, and noticed this. The first photo shows the whole crystal. The second is a close up, and the last is an extreme close-up. There are specks of galena on the quartz, but not crystals. As far as I can see with the microscope, there are none of these specks included in the quartz.
I also took some close-up photos on the end of the quartz crystal which attaches to the matrix. It looks like it is damaged at the end that attaches to the galena but not the other one.
Another interesting feature of this piece are lines on the surfaces of the galena crystals. The lines tend to be roughly parallel but curve. Photos:
The other piece not known to be fake
Now I will show some photos of the other piece that is not known to be man-made. It is different because instead of having hollow cubes, the galena's shape is more like a loop. Here are some photos of the whole piece:
I also took some close-up photos. The photo on the left shows shows a small quartz crystal growing out of the inside of the galena "loop" and the one on the right shows that there is some galena in or on a quartz crystal. This piece does not show the curved pattern of lines in the same way as the other piece. These line appear more random in their path. Another observation about this specimen is that the galenas have small shiny spots in seemingly random places.
The first man-made galena
Both of the galenas I have that are known to be man-made were created through microabrasion. Here is a full photo of the first one:
I also took a close-up of the inner bottom surface of the piece. Interestingly, the microabraded surfaces of the galenas displays a pattern of curved, parallel lines extremely similar to those shown on the first galena we received from Edward Rosenzweig:
The second man-made galena
Here are some photos of the other galena I have which is known to be man-made.
A full view photo:
I also took some close up photos. These show that this galena, which was created with microabrasion, also has the pattern of curved lines that the other two pieces show. But the lines are not as well defined as in the other pieces.
SEM photos/Conclusion
Lance Kearns offered to examine these specimens with the SEM at James Madison University. He let me stay in the SEM room while he was looking at them so I could see the images also. Because of a time limit, I selected three specimens to examine: one that was definitely man-made and two unknowns.
I looked at the man-made one first so that I could see what to look for in the other two. It had spherical indentations in the surface:
We looked a little more at the same sample and noticed a glass sphere, which was left-over abrasive material. That wasn't really a discovery because we always knew that piece was man-made, but it did help show us what to look for!
The next specimen was one of the unknowns (A)
Soon we noticed a glass sphere partially embedded in the surface of the galena, with craters and cracks around it.
Last, we looked at another unknown (B)
Like the other two, this one had craters in the surface:
There were also aluminum silicate crystals. We used the computer in the same room as the SEM to research and learned that aluminum silicate is widely used as an abrasive. The cracks coming from behind the aluminum silicate crystals (especially obvious on the third crystal from the left) are also evidence that the crystals are left over abrasive material.
Ending Notes
This is also published in Mineral News magazine December 2010.
Because of the time limit we were not able to look at more than 2 unknown pieces, and the fact that these 2 were fakes DOES NOT mean that all similar pieces are!! The only test that was able to tell the difference was the SEM and without a much larger sample size it is unfair to draw any conclusion about all hollow galenas - only about the 2 that were tested.
It might be easiest if discussion about this article continue to occur in the following thread http://www.mindat.org/forum.php?read,55,157736,page=1 rather than in this article, where the posts may become unmanageable.
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