Bob Harman
Joined: 06 Nov 2015
Posts: 765
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Posted: May 13, 2019 10:32 Post subject: Artificially dyed agates = a legitimate use of water |
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Most of us who have been to mineral shows have seen the artificially dyed agates. Many colors are possible. The dyes penetrate into the agate's microcrystalline quartz structure making them not just lustrous, but able to hold the dye color for long time periods.
But no self respecting mineral collector actually buys these things...........
Then, about 2 years ago, it suddenly occurred to me that my fresh field collected pleasingly blue colored chalcedony geodes from right out of the limestone matrix, here in Indiana, are also microcrystalline quartz. Pretty much mineralogically identical to the structure of the agate!
This was very important as, for years, I had put my self collected examples onto shelves and display cases, only to see them very very gradually dry out and become, not only less lustrous, but paler in blue color. In situ, these blue chalcedony geodes were being kept blue by the water in the surrounding matrix limestone which, very gradually, over millennia, was leaching water well into the microcrystalline quartz structure of the adjacent geode.
Into water went my examples and now kept under water, with a splash of bleach, in plastic storage boxes. Along with luster, the intense blue color seems preserved. Only time will tell if those specimens that have already paled out will reabsorb enough water to regain their bluish tint.
Altho previously pictured, here are several of the examples kept under water, except for show displays. Bob
Mineral: | Quartz (variety chalcedony) |
Locality: | State Route 37 road cuts, Harrodsburg, Clear Creek Township, Monroe County, Indiana, USA | |
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Dimensions: | Larger half is about 15 cm |
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Crystalline quartz on blue microcrystalline quartz (chalcedony) Self collected 2017. Kept under water, except for displays, since collection. |
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27234 Time(s) |
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Mineral: | Quartz (variety chalcedony) |
Locality: | State Route 37 road cuts, Harrodsburg, Clear Creek Township, Monroe County, Indiana, USA | |
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Dimensions: | about 10 cm |
Description: |
Microcrystalline quartz (chalcedony) Self collected about 10 years ago, now kept under water for 2 years |
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27190 Time(s) |
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Mineral: | Quartz (variety chalcedony) |
Locality: | State Route 37 road cuts, Harrodsburg, Clear Creek Township, Monroe County, Indiana, USA | |
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Dimensions: | about 12 cm |
Description: |
Crystalline quartz on microcrystalline quartz (chalcedony) Collected about 12 years ago, after paling out, this example appears to be gradually regaining some bluish color after being put under water about 2 years ago |
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27220 Time(s) |
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