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Geology/blue rock picture


blue rock I
blue rock I  

blue rock II
blue rock II  
Here is angle of the rock I am trying to identify.

This is very difficult without actually seeing the rock but I believe that it is one of two rock types.

Fulgurite, would be my first guess, is the varietal name given to fused Quartz, Si02, which has been fused by the action of lightning striking the Earth and locally melting the sand. The best known Fulgurites are found in Quartz sands, where the Fulgurites take the form of tubes, sometimes exceeding a half inch or more in diameter. This type of formation is called a Sand Fulgurite. As the lightning strikes the Earth and courses downward through the sand, the sand is instantly super heated (i.e., melted and fused). After cooling, glass-like hollow tubes (Fulgurites) can sometimes be located beneath the surface of the sand, generally decreasing in diameter and sometimes branching as they descend, sometimes extending for several feet. The outer surfaces sand fulgurites are often rough with adhering, unfused Quartz sand grains. The inner surfaces and openings of the tubes are usually smooth and glassy, in some specimens resembling an applied glaze, sometimes with blister-like bubbling present.  Rock Fulgurites are formed when lightning strikes the surface of a rock, melting and fusing the surface, and sometimes the interior of the rock.  The melting point of Si02 is 2950oF. The color of the glassy, fused Si02 varies from pale gray, to smoky gray, to shiny black. The name Fulgurite is from the Latin: FULGUR (lightning).

The main reason that I believe that the rock is fulgurite is that it is very unlikely that serpentine is found in or near London; since it is a metamorphic rock.  If the rock was found in or around London I would think that it is fulgurite.


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Joe Norris


I am an economic geologist. An economic geologist does mineral evaluations and appraisals of mineral or mining properties. I can tell you if your deposit has value - remember that a mineral deposit, no matter how good, only has value when mined. Any value assigned to a mineral deposit, in the ground, is only the speculative value that deposit.


I have been a economic geologist for most of my 35 year career. Although I have done work in perhaps 45 states and numerious countries much of my work has been in Appalachian coal, intermountain west gold and silver, and Arizona uranium.

Past President of the Virginia Section of the American Institute of Professional Geologists and a certified geologist in twelve states.

BS Degree from Eastern Kentucky University. Work on MS Degree @ Eastern Kentucky University, Colorad School of Mines & Marshall University Numerious short courses on the value of mineral deposits and how to value same. Also several short courses dealing with the different types of geologic processes; sedimentary, igneous, metamorphic along with the mineral associated with each.

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