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Crystal Oddity Encapsulated in a Blue Fortification Agate

Crystal Oddity Encapsulated in a Blue Fortification Agate

By /October 7, 2022 /1 comment /Cut Rocks

This is a cross section of a blue agate nodule from The Carver Agate Field. Rock #4914 The small nodule, approximately 2 inches across, was initially cut and lightly shaped to capture the fortification agate in the center of the stone, as well as the ‘white eye’ on the left-hand side of the stone. And for even more interest, there was a contrasting brown spot on the upper right-hand part of the stone. That explains why I was cutting this stone in the way it was cut. Rock #4914 magnified Well, once cut and polished and subjected to modest magnification, the brown spot suddenly and unexpectedly became the highlight of the stone and the subject of this blog. Magnification, as shown above, produced a highly angular brown crystalline structure and not shards of broken or fragmented stone encased later in the agate. When this agate nodule formed inside of a […]

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A Ghost and Four Other Carver Agates Cut This Week

A Ghost and Four Other Carver Agates Cut This Week

By /October 2, 2022 /2 comments /Cut Rocks

The most interesting of the five stones is the “ghost,” shown below in two different angles. Click each image to see an enlarged version. Rock #4910 Rock #4909 Next we have a yellow fortification agate in an “octopus garden beneath the sea.” Rock #4894       Photo 4906 below is the slab from another nodule creating a cut and polished agate which looked blue before being cut and more red to orange after being fully polished.      Rock #4906 Rock #4906 close-up Photo 4896 is a jasper/agate free form designer cab. I just liked the colors.     Rock #4896 For the lapidists out there, photo 4899 below, which I call the flower garden agate. is the most interesting cut that I have done in a while. Usually I take a nodule, cut a thin slab from a crosscut of the nodule, and then grind and polish, as is the case in all […]

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Flower Garden Agates

Flower Garden Agates

By /January 17, 2022 /1 comment /Geology

This is why I love cutting material from The Carver! Rock 4582 Rock 4538 The oval flower garden agate cab has a white fortification agate in the center. A fortification agate is named for the pattern that would be seen on the ground if one were looking down from above upon an old-fashioned fortress—think Fort Ticonderoga. (See Gemstones of the World, by Walter Schumann, page 134, 1977 edition, for discussion and photos of the fortification agate.) The point of this blog, beyond the beauty of these flower garden agates, is that it is very complicated and difficult to exactly identify a particular type of agate, particularly when many agates contain within them several identifiable specific types of agate. Ergo, this is a flower garden agate with a fortification agate in it. Rock #4538 Detail

New Year Powder Blue Fortification Agate Bracelet

New Year Powder Blue Fortification Agate Bracelet

By /January 3, 2020 /0 comments /Bracelets

This bracelet and its powder blue agate stone were created just before Christmas 2019–the only bracelet I made in 2019. It is a great start for 2020 and is gemologically interesting. Though at first, this blue agate may merely seem beautiful and elegant, it is much more, particularly if you like rocks like I do! First, the lower right hand corner of the stone has a half moon shaped blue area of finely banded agate. This fine blue banding displays opalescence, e.g., its blue color and reflectivity subtly changes depending upon the intensity and type of light (natural, incandescent, fluorescent, LED, etc.). Second, the orientation of the stone to the light will change its reflectivity and brightness.  This is very much what you would see with certain types of precious opal.  Third, the fortification agate (named so because it has a shape with angular corners, like looking down from above […]

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