Staurolite has escaped mineralogical obscurity because of a single trait: Its tendency to form twinned, prismatic crystals that sometimes intersect in the universally recognized configuration of the Christian cross. For this reason alone, staurolite is a favorite at rock shops and gem and mineral shows. It is widely collected, steeped in legend and lore, worn as a goodluck charm, honored as an official state mineral and celebrated as the namesake of a state park.
THE MINERAL
Staurolite, a basic iron aluminum oxysilicate, crystallizes in the monoclinic system. With its Mohs hardness of 7.0 to 7.5 and relatively high specific gravity of 3.7 to 3.8, it is somewhat harder and denser than quartz. Staurolite’s colors range from yellowish-brown an d reddish-brown to brownish-black.
Staurolite has a metamorphic origin and forms from the high-grade alteration of shale. It is primarily hosted by schist, a medium-to-coarse-grained, silvery-gray, foliated, metamorphic rock. Staurolite is closely associated with kyanite, sillimanite, and andalusite, the three polymorphic forms of aluminum silicate.
VIRGINIA & GEORGIA
In the United States, staurolite occurrences are concentrated in the highly metamorphosed rock of the Appalachian Mountains that stretch from Georgia to Maine. Georgia’s most productive collecting sites are found in the northern counties of Cherokee, Fannin, Pickens and Gilmer at such sites as Sharp Top Mountain and Turkey Hill. Recognizing its great popularity among collectors, the Georgia Legislature designated staurolite as the state’s official mineral in 1976.
This story is from the Rockhound Roadtrip 2024 edition of Rock&Gem Magazine.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the Rockhound Roadtrip 2024 edition of Rock&Gem Magazine.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Sign In
THE BRIGHT SIDE OF VOLCANIC ROCK
As a mineral resource, volcanic rock is decidedly short on glamour.
The Other Copper Minerals
12 Lesser-known Collectible Species
MINERAL COLLECTING -AND ROCK & GEM
Evolving Together FOR 54 YEARS
Gemstone Trends
A Look Back at 2024 & What to Expect in 2025
How to Make a GEM BEAD NECKLACE
No Lapidary Experience Needed!
Framing Nature's Art
Faceting Rutilated Quartz for Beginners
BEDAZZLED BLUE SEAM AGATE
More than several centuries ago, mining was the profession most often seen as befitting of men.
ROCK & GEM FIELD GUIDE:
Spinel is a captivating gemstone with a rich history of being mistaken for gems like ruby and sapphire.
SNAKE SCALE DROP 1.5:1
This Faceting Focus is revisiting the briolette gemstone design because of its popularity with independent and hobby gemstone faceters.
STONE CHIC
How Earth-Inspired Decor Brings Comfort to our Home