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![I found the the rocks is Eastern Arizona by the Black Mesas. They are white with a few orange patches. The inside kind of looks like quarts.

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closed as off-topic by Leukocyte, arkaia, Fred, Peter Jansson, trond hansen Jun 25 at 4:43

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It looks to me like a type of flint. Flint nodules are found in chalk and some types of limestone. By banging them with a hammer, you should be able to strike off curved chips with sharp edges. Fractures of flint typically show a conchoid (shell-like) curve. The interior of a flint nodule is brownish, with a glassy texture, but the exterior is often white because of its association with chalk.

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    $\begingroup$ The safest description of the stones is to call them cryptocrystalline quartz, the common names could be anything from Flint (typically associated with lime deposits) to Chert, Chalcedony (if clear), Jasper, and others. All develop when silca is leached out of the surrounding terrain and redeposited in another location. The rocks don't have an easily identified crystal structure and typically fracture with a conchoidal fracture, ie like glass. For your rocks the silca comes from lava's with high silca content. The white coating could be common opal, frequent in Arizona. $\endgroup$ – Friddy Jun 24 at 21:21
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Agree with the first reply. It is flint. Also known as chert. The composition is Silica Dioxide (SiO2) which is the same composition as quartz. You'll get all different kinds of SiO2 out there with varying names based on the structures in the rock. Agate, chert, calcedony for example.

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