Novaculite
“The razor stone”
Sedimentary
Novaculite is a dense, extremely fine-grained siliceous sedimentary rock closely related to chert. Its remarkably uniform microcrystalline texture has made it the world's premier natural whetstone material for sharpening blades for centuries.
Composition
microcrystalline quartz, traces of clay, organic matter
Where Found
Ouachita Mountains (Arkansas, USA — primary source), Oklahoma (USA)
Mohs Hardness
6.5-7
Fun Fact
Arkansas novaculite whetstones have been traded for over 10,000 years — Indigenous peoples valued and exchanged them long before European contact.
Test Your Knowledge
What geological process gave novaculite its uniquely uniform grain size suited for sharpening?
Related Specimens
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