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Geology/dad found this stone

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Question
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Can you help me identify this stone . It looks diffrent than most because it has perfect angles like it hasnt weathered much almost like a cut gemstone.

Answer
The rock is Jasper, variety bloodstone.  Jasper is a variety of quartz and comes in a variety of colors depending on the impurities contained. The variety of your rock, bloodstone, has minor iron in it which causes it to red or brownish red.     

Jasper, an aggregate of microquartz and/or chalcedony and other mineral phases,is an opaque,impure vauriety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to iron inclusions. The mineral aggregate breaks with a smooth surface and is used for ornamentation or as a gemstone. It can be highly polished and is used for vases, seals, and snuff boxes. The specific gravity of jasper is typically 2.5 to 2.9. Along with heliotrope (bloodstone), jasper (green with red spots) is one of the traditional birthstones for March. Jaspilite is a banded iron formation rock that often has distinctive bands of jasper.  

Pure quartz, traditionally called rock crystal or clear quartz, is colorless and transparent or translucent, and has often been used for hardstone carvings. Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, jasper, and others.

The most important distinction between types of quartz is that of macrocrystalline (individual crystals visible to the unaided eye) and the microcrystalline or cryptocrystalline varieties (aggregates of crystals visible only under high magnification). The cryptocrystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macrocrystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite. Other opaque gemstone varieties of quartz, or mixed rocks including quartz, often including contrasting bands or patterns of color, are agate, carnelian or sard, onyx, carnelian, heliotrope, and jasper.

I couldn't get the photo to paste but below is the link to a crystal picture of citrine which is very similar to bloodstone. When minute amounts of contaminants are contained in quartz the resulting rock has a very lessened propensity to form crystals.

http://us.cdn1.123rf.com/168nwm/hapelena/hapelena1305/hapelena130500020/19694943

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Joe Norris

Expertise

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.

Experience

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.

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

Education/Credentials
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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