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Geology/Identification of this rock or mineral?


Rock or mineral
Rock or mineral  

Rock or mineral
Rock or mineral  
Hi, I've had this rock sitting around my house for a while, I wanted to know what it was; and if it had any value? Looking forward to hearing from you.  Thank you for your time.

The rock is quartz in crystal form.  The colors are mostly from very minor amounts of iron that were in the original fluid of the quartz.  The biggest problem that I have is how in the world did it get to Florida.

Crystal system: hexagonal. Fracture: conchoidal. Color: colorless or white, but may be tinted various colors (e.g., purple, amethyst). Hardness: 7.0. Streak: colorless. Luster: glassy. Specific gravity: 2.65. Uses: jewelry; prehistoric arrowheads, knives (flint); gravel (chert).

Quartz is the main constituent in sandstones and geodes, and also occurs as vein quartz. Crystals usually consist of six-sided hexagonal prisms capped by pyramids on one or both ends. Quartz crystals are found in geodes that occur in several different rock types, particularly limestone. In south-central Kentucky, valleys and stream beds downslope from the Warsaw-Salem Formation are filled with geodes, some containing amethyst (another variety of quartz).

Several cryptocrystalline (microscopic crystals) varieties of quartz occur in Kentucky. They are commonly recognized on the basis of their fibrous texture and granularity. The fibrous varieties include chalcedony, agate, onyx, and jasper, and granular varieties include chert and flint. See the links to photos below


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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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